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Hedges and lawns

Around here, most hedges are made of boxwood, or privet

dodoneae or podocarpus fern pine

pittosporum is popular too

or on occasion – griselinia and escallonia.

Gas station hedges are made of raphiolepis.

Look under the hedges for the irrigation spray heads or drip lines or soaker hoses

Oftentimes, there isn’t any

in clay soils, these plants require no additional irrigation once established.  

That is the key – once established.

For most shrubby woody plants in the clay loam soils

it can take two or three years of winter rains and intermittent summer irrigation

for the roots to sink down wide and deep, and for it to be well grounded

after that happens, you can come by once every couple of months to shear it to shape

and it does not seem to mind

it resprouts a wall of greenery right away without any problems

cause it has reserves, cause its embedded in the landscape

it helps that these plants

often have small waxy leaves somewhat resistant to desiccation

it helps that these plants originate from places with much much hotter summers

compared to a foggy coastal place like san francisco

if these shrubs are growing in the west side, in the sand

perhaps in the lean of a shadow of a house

they can still get by with no additional supplementary irrigation

they might get a little stressed after four or five months of dry weather

drop some leaves, turn a wee bit red or yellow

but they usually pull through alright

If they are established

and the rains come

aside from the usual suspects

there are a number of other plants that fit the criteria of a useful hedge

plants that grow a thick and full bush of smallish leaves

plant that sprout out readily even when cut back, even to bare wood

Plants that do not go leggy and tree-like and lanky on you

plants that are uniform and green green green all year round

What you don’t want as a hedge plant 

is a plant that is finicky and temperamental after a hedging operation

some leafy parts go vigorously nutty

while a whole nuther section just dies, leaving a gaping hole

Those plants you want to avoid, they are no good as hedges, better in their own natural shape

Ceanothus is one of those:

A few other drought tolerant plant choices (once established) are:

True myrtle Myrtus communis.  Can you guess where this is?

Eleagnus umbellata is another great plant. The silvery leaves, plus the edible berries for jam. What is not to like about autumn berry?

Africa boxwood Myrsine africana shown here with Myrica California in the background and Quercus agrifolia in the foreground on the side.  In our cloud garden.

Way old stand by from forty fifty years ago Juniperus communis.  All along Teresita.

Heres an interesting specimen. Leptospermum scoparium as some kind of a sidewalk bonsai hybrid hedge thing.  We’ll just say that it may have potential.

Breath of heaven Coleonema pulchra.  Like all hedges, gotta stay on top of em.  If you fall asleep with Rip Van Winkle,  the plant grows tall & wide.  Then when you prune it hard down to all bare wood, it may live, or it may go into shock and die.  Or it will die back in sections here and there, and there goes your full green hedge concept out the window.  So like mowing the lawn – be consistent and keep trimming trimming and trimming on a regular basis.  Dont take off too much in one hit.  Do not neglect it.

Hedges – a living wall, a breathing border, a wave of greenery

pretty neat garden sculpture

a sculpture that comes back to life as soon as you’re done with your role as a gardener

Around here, most lawns are like mutts

they are a mix of plant species

if you go to the golf course or the lawn bowling green

theres patches of pure good sod – all fescue, or all bent grass

but most other ‘lawns’, at least in open public places

All full of daisies clover dandelions plantain veronica cat’s ears

and the grasses are a mix of fescue and poa and bermuda and rye

if you are not a discerning turf expert, you probably don’t even notice its a mix

once it has been mowed to 1.5” tall

and its all trim and uniform

that is what you see, that is all you see – a carpet of green

It does take considerable water 

to keep the lawn green

like the hedge, we like the lawn to be green year round

if we did not water the lawn, it would  go dormant, dry, and brown

that is what happens to the grasses in nature, during the dry season

to keep it full of life, water that lawn

the green color  – its so soothing

Lets say you want a flat usable space, a patch of greenery

but not one made of water-hungry always needs to be mowed grass

What are the alternatives?  

What is another plant that you can 

Step on, lay on, walk on, roll around on?

And you say “No, I do not want round tiny gravel or artificial turf or decomposed granite or slabs of concrete or slate or flagstone with a weatherproof carpet on top.  I want something soft, something gentle”

A pretty tough ground cover is Dymondia margaritacaea

A friend in the east bay tore out the lawn, and knitted it back together with a native plant ground cover called Lippia repens.

Dichondra always shows up on these lists.  My experience is that with a little bit of walking on em, the leafy ears start to crumble and then its lights out. Left alone it is has solid coverage.  With interaction it gets patchy.

The following particular choice is controversial, both among the native plant activists and amongst some rank and file gardeners.  Arctotheca cape dandelion.  Some people say it is a ‘nonnative invasive weed’. It does have those ‘I’m gonna take over’ tendencies.  At the same time, it restricts itself to mostly wet soils and shady exposures.  That is to say, it does not rule in the south side, it does not do well in the uplands.  It is the boss, however, on the north side, and on the bottom of the slope where water gathers.  It completely replaced the CCSF entrance lawns on Phelan Avenue, and has persisted year after year after year.  Nope its not the lush paradise lawn manicured turf like at USF. But then again, it wins on a lot of other criteria, and our windy foggy commuter campus is not the kind of place where people are lounging around in designer gear. They are working! What do you think?  Reach for the round up?  Get out the rototiller?  Or leave it alone?  

There is some room for entrepreneurial spirit in the turf alternatives world.  I imagine a good second choice would be a meadow mixture comprised of say three to five different species of plants.  They would all be okay with mowing, and be more or less drought tolerant once established.  They’d be plants that are a little less needy with regards to fertilization and pest control.  Seeds could be sown in a flat, and grown up into a tight mudflat quilt ready to be transplanted or divided and grafted into the ground.  You would have to play with the water regime to figure out the evapotranspiration rate and the best watering schedule to keep it green, to let it establish.  Aside from the general mutt lawn mix of dicot broadleaves we already noted, there are many other possibilities to experiment with and dream up.

How do you irrigate something that needs water all throughout the dry season, and still be frugal and conserving?  You have to irrigate like the rain that comes down on everything everyone – drip drip drip drip drip in tiny little droplets.  Not gushin big spurts.  Nice and slow tick tick tick building to a crescendo storm of pelting drops.  Wet it all the way down down down.

Visualize the earth as a huge sponge with tiny tiny holes all over her.  To get in there, as water, you have to get tiny tiny too.  If you try to push your way in, but you are large and stuck to yourself, then you will not fit.  You will have to be fine and patient, that is the trick. Well plus it helps if the soil is not hydrophobic. Organic matter organic matter.

Xeriscaping: Gardening with native plants, gardening for wildlife, gardening for restoration

The xeriscape planting process is easy. This next part of the discussion is bundled into a huge knot. I don’t know if I will be able to explain it well and loosen some of the tied up tension. Perhaps better to stay clear to avoid metaphorically pinching a nerve or falling into a ditch or getting hit on the head. But like my friend Joey tells me, when in doubt, paddle out. So here we go.

So theres a shift. Rather than imposing our garden style on nature, we are going to listen to her, and go with the flow. If theres a lot of water, use it. If theres not so much, conserve it. Common sense. But what if the king, who controls all the water, says “I don’t care, all the water for me, y’all get the left overs”. “Y’all” meaning poor people, salmon people, wildflower people, and rainbow people. Then you say, “Hey that is talking about morals and politics and class, like stratified class, not a college xeriscape class, we didn’t come to discuss stuff like this. That is for sociology or political science or religious studies or law school” Okay, skip it then. Stick to the curriculum.

Back to the shift. For many years nobody cared about growing California native plants. They were not used in landscaping. If there was mountains and valleys full of the stuff, why would you plant it in the garden? It is like – do you go to a zoo to see a raccoon and a pigeon, or to see a tiger and an elephant? Are the natives even showy? No! What you wanted was an exotic orchid or a huge gorgeous rose or the latest hybrid everyone is gushing over, not some hard scrabble drought tolerant ugly thing weird looking thing that come out of the universe’s twisted imagination. Beauty was defined by the old folks from the east, from across the seas, not embodied or dreamt up or personified in the landscape around you.

Then the natives caught on like a fuse of gunpowder about fifteen twenty years ago. In every public space that the landscape architect planned – natives. In every new installation or design magazine – natives. It became the new hip thing. It didn’t matter if the plant did not fit in the site, it was ‘native’! Like so happens in the this-or-that sphere of public affairs, native became synonymous with good. So if you were a righteous kind loving person, you better go ‘native’.

Some of you probably don’t even know what a native plant is. Well that is a made up term for plants that have been here in California since around year 1540, or longer. Plants that have been around for the past ten thousand years or so plus or minus. Plants that were present before the Spaniards and Russians and French and English and Irish and German settlers came and displaced the Miwok and the Chumash and the Achowami and the Pomo and the Modoc and then opened the gates to the Lao and the Japanese and Yugoslavs and Hindus and Nicoyas and anybody else from around the world. The Mexicans, well they have been here all along; perhaps they were called Kumeyaay or Kiliwa way long ago… Thus, there are these native plants that have persisted, and there are introduced plants. Introduced plants that came as seed on ships and in shirt pockets, in the guts of sheep and stowed away in bales of hay. They were brought here by immigrant settlers travelers for animal food, for human crops, for gardens, and so on. If you don’t go hiking around to natural places, if you are mostly a town dweller, then most of the plants you have met are probably non-natives. So theres natives and non natives – if you want to divide them and make it clean cut, easy to label. Its actually a really mixed up matrix already, and bound to mix more, not less. In the continuum of time, they are all just plants.

To stay on track – you can plan and design a xeriscape garden, but once it is in the ground, you do not get to control it, nor do you really want to. If you took your measurements correctly, the tailored suit should fit just fine. Same with the landscape, if you were careful with observations and made the right selections, the plants ought to ‘perform’ as indicated. And over time, nature she will play with the patterns and make it her own. Then you will do adaptive maintenance. Its like a fun dance, not a war of wills. Plants may come in by themselves, plant that you elect to keep. Other plants that come in, you may decide to weed out because they tend to take over. A low maintenance xeriscape garden does not mean no maintenance. Take a heading, set a course, but be prepared for currents and swells. Again, same lesson. You want to listen to the land and plant accordingly. If you have an artificial culturally bound goal, (for example, I only want 100% native plants), you will be frustrated when it is not pure and then you will fall into the pit fall trap of fixed ideology (angry with fists clenched, ‘it has to look like this!”). The trap of viewing the garden through the dichotomous mind rather than perceiving it as it is (the sort of thinking that ruins the whole scene). Now you are like – “Hey this is not a philosophy class or some hippie dippie meditation martial arts class! Get on with it!”. Sorry, pass. Pass. Pass.

Many of the native populations have suffered. Again, we are talking about plants, not people. Plants. Some of them evolved in the clay riverine drainage flats of the central valley. As the soils were plowed and converted to large tracts of farm land, the plants either disappeared or shrunk and shrunk their range. In some hilly grasslands, cattle were let loose. If the cows were to munch a munch and move on, the plants could recover. But if the cows were fenced and walked back and forth, back and forth, then the carpets of annual flowers eventually caputted and faded away. Here in San Francisco, as the western dunes were developed to make way for people, the flora of the sands got bulldozed into oblivion. And with the flora went the insects that depended on them for food. Hence, the first couple of butterflies to go extinct in North America happened right here – a couple of dinky little blue butterflies by the names of Xerces and Pheres. Right here along Ocean Beach and the Sunset Richmond and Marina green neighborhoods.

Then what do we do? Cant go backwards, only forwards. For people distraught about all that has been lost and destroyed, the goal is restoration. Restoring native habitats. This is happening in the grassland prairies of the midwest, the wet soggy woods of the northwest, and the wetlands of the bay area. Restoring some of that diversity that once existed, re energizing some of that connection ancient peoples had with their land. This is a neat challenge that utilizes many of the same principles as xeriscaping – planting with the rains; fitting plants to the specific site according to water, light, soil; planting for desirable wildlife. Most important though, as far as restoration is concerned, this is about restoring the love that native peoples have for the earth. And by native I do not mean measurements of blood lineage or your ability to make a sinew bow string or your agility to ride a horse, I am talking about being part of a place and a community, of being grounded.

You know, native, in the best sense of the word. Not native like in native versus cosmopolitan, like you never left the street you were born on. Not native like in native versus educated and cultured. Like you are ignorant and without manners and don’t know anything about hygiene. Native meaning proud, protective, working with, and on behalf of, all the creatures big and small, young and old, healthy and infirmed.

I dont know about how and when you grew up, but it seems to me that much of this generation of children may be the first to grow up with absolutely no clue as to their relatives and kin in the natural world. The wild kin. Not the kind you have to pay to see, not the pestiferous ones always following us around, not the pets in the house. Wild kin that are independent, going about doing their own thing: goofing around, talking to their friends, raising their families. By no clue I mean that kids don’t know them alive, in person, hands on. These days, all those kin are either sitting dead in a glass case, jailed in an outdoor museum, verbally dissected on a screen, or so far away as to become mythic creatures. Yes there a few kids that gut fish, or shoot 22’s, or harvest tomatoes with their mom, or go picking apples in trees, or paddle a canoe, or make a fort in pine woods. It would be nice to see more. More kids actively engaged with the natural world.

If you are a kid who grows up without ever having damselflies land on your fingers, or butterflies flitting around your head, or hummingbirds zapping back and forth in your vision, what does that do to your imagination? Or your psyche? What kind of a sterile lonely place would a mind retreat to, when it is devoid of fellow sentiment majestic forms? If you had to count the monetary cost of such a transaction, would your calculator be able to hold all the zeros? Well, easy to get overwhelmed by the world’s drama, best to open the door out back. To the ranch and the farm and garden and the plants – to work. With a shovel a pick and a handful of seeds, and wait for the rains to come.

Alright, where’s the action? Well in the past years gardeners and academic entomologists have been working together towards the conservation of insects. You can help by planting native plants, planting forage and nectar plants, and planting caterpillar host plants. You can make trendy solitary bee homes or leave patches of open sands for them too. A UCB professor who specializes in bees, Gordon Frankie, has been hard at work alongside nurseries like Annies Annuals and curators like Dr Don Mahoney of the San Francisco Botanical Garden. These folks have been advocating for these beneficial creatures that help pollination and pest control. Dr Don gave us a tour of his garden, and discussed how he maintains his fantastic collection of plants. It is not xeriscaping per se, but it is close to gardening in a way that the natives would appreciate. Please watch his two part video here for specific tips and advice about habitat gardening:

As a gardener, you do have to come to terms with life and death. It is a part of all the interactions in the field. If you want to grow and protect the plants, you will have to help them against their foes. Doing nothing or letting nature takes its course just means that you are neglecting your duties. For example, with regards to gophers, you could use cultural measures to stop them, like the use of gopher baskets. But, time to time, you may have to trap them and kill them. Same thing with the weeds. Take care of them, you’re the gardener.

You are an active manager of the wildlife in the garden; one who is tasked with the balance and health of all the species. I will tell you right now that it is not an easy job, and real messy too, but necessary. There is a discomfort that comes with death. In the amazonian universe the hunters go into the rivers or under the earth in dream state to negotiate with the master of animals. Its a back and forth as a caretaker of the jungle and a taker of life. You realize that it is a reciprocal relationship to maintain the fecundity and abundance of all creatures. It must be approached with respect and gratitude, otherwise it will all go to poop. Whoops I think I strayed off topic again to mythology and anthropology or rainforest conservation or some other unrelated topic. Xeriscaping – it is about water, plants, the land, and life. Water is the ultimate connector and universal solvent and most and least common denominator. That is how it is all tied together.

This third set of plants are plants found in the sandy dunes, the clay uplands, and plants useful for raising butterfly larvae. Most are natives, not just California natives, but San Francisco natives. A few are from other places. Some of these we saw on our walkabout to the Ocean Beach dunes off of Judah Street, the rest we will hopefully encounter another day.

This is nutka reed grass in our cloud garden:

In the dunes, plants holding and stabilizing the blowing sands:

This second set of plants are from areas south of here. These include Southern California, Australia, and South Africa. So the criteria for selection is more climatic and geographical, unlike the first set of plants – whose selection was based on its succulent morphology and physiology.

This set plants come from a climate that is, for the most part, hotter than ours. So the plants can take the heat, and the dryness. These plants have been chosen because they are sometimes seen in the San Francisco Bay Area; also because they are not plants you learn in our CCSF Plant Identification classes OH 76 & 77. They are plants that are amazing to behold in the garden setting. Definitely ‘worthy’.

Keep in mind that these are a minuscule representation of the flora of these places. They are just a piece of bait, or an easy freebie, to entice you to explore the diverse flora of the world, and begin to cultivate some of that freedom.

Lets head out to the Channel Islands, San Luis Obispo chaparral, alkali lakes of the desert, and coastal scrub of San Diego.

Now cross the Pacific Ocean and check out some botanical kin down under.

Finally take a sail past the Indian Ocean, cruise along Madagascar, and on down to the Cape of Good Hope.

How will we learn these plants? Scavenger hunts, walkabouts, propagation, and planting them in the garden. Stay tuned, more directions to come. This is only the list…

Wild rosemary and Felicia, all African in origin:

California fuchsia in the cloud garden, small tree in backdrop is wax myrtle Myrica californica:

South of Judah on La Playa, right past the bocce ball courts of decomposed granite:

Xeriscape process: How to plant the garden

Theres the long range and the short range.

If you are a farmer who plans to work the land for forty or fifty years, and maybe pass the land on to the next generation, you would try to take real good care of it. You want the earth to stay healthy and abundant, and to make it better, not worse.

If you are a landscapers working at a shopping mall or some kind of a commercial type property, then you know that the plants are just decoration and temporary. The next owner who flips the house will switch out the garden in five or ten years, the new manager will say ‘Cut it all down’ and put in a garden based on the latest trends. The plantings are disposable and short lived, and so you work accordingly.

In a short term planting plan, you bring in new top soil or potting soil, and just lay it on top. You do not have to mix it or till it in with the native soil, since the plant roots are going to be shallow – the upper 12” or 16” or so. You hook up an irrigation system to make sure that the plants are watered with good coverage. You do not anticipate that the plants will ever reach down deep or wide to find their own source. You lay down a layer of weed cloth, then cut some holes in it for the plants. You throw the plants into holes in the ground, not bothering much to open the root ball, or tease and cut out the girdling roots. Time is of the essence; you know that the plants are not going to live that long anyways. To finish the planting you spread a layer of small bark mulch on top. Thats it, you are done.

For the most part, the xeriscape garden is more the long range plan rather than the short range one. It requires you to pay attention to the soil and the water. You want your plants to be well settled into their places and take care of themselves, not always be dependent on external supports and high maintenance regimes. You imagine and hope that the plantings will still be prospering forty years down the line, although you may not be present anymore to witness them.

So the first thing is to plant according to climate. Microclimate to be specific. Meaning that you find the minor tiny variations in a given place, and match your plants accordingly. Observe your garden and surroundings with tremendous intensity. Even in a hot hot place, there may be a shaded spot near the eave of the house that is ten degrees cooler than everywhere else. Write this down. Next to the driveway, there is a spot that is perpetually wet. You are not sure if it is the roof runoff, shallow groundwater, or what?, but it hardly ever dries out. Water always gathers there. Write this down. And you look at the neighbor next door – they have a fifty year old lemon tree that is always blooming, always full of fruit. You see them using it for cocktails, kids squeezing lemonade all the time. You strike up a conversation with the neighbor – how often do you water the lemon? Do you fertilize it? And the neighbor says “I don’t do anything! It just loves the exposure and the soil, I guess…”. Plant something that likes that little niche you have discovered, not a plant that will be distressed and uncomfortable. Make the plant feel ‘at home’.

The second thing is to work the soil. Some of the ornamental xeriscape plants we are planting do not need much amendment, actually. They might have come from a place where poverty was the norm, and they are not really enamored of rich rich soils. They be like ‘Whats the big deal? I’m fine with rice and beans, and a bit of chile pepper. I dont want to eat beef and pork and shark and tiger and bear every meal. That is for the kings and queens. Rice and beans for me!” Other plants we are planting do like a bit of help to look good in the garden. So that is what we will do. First is to amend the soil and mix it in. That is in every garden help column and every horticulture magazine – add organic matter. Add it to sandy soils, add it to clay soils. Make goopy globs of nutrient humus and worm heaven and increase the soil’s water and nutrient holding capacity. Make uneven pores and holes to improve the drainage and aeration. What kind of organic matter? Manures and composts always excellent, as are the fallen leaves and worm poop called castings. The other thing to do with soil is to shape it. This is making terraces or little berms and mini volcanoes, pressing them into shape and form, so that water will better infiltrate the ground. Actively direct the flow of water, whether that be from irrigation or from rainfall. This little rhododendron is gonna like all the water it can get…

As the weather starts to dry, the soil forms this glaze of a skin over itself. As if it were a creature itself that was conserving moisture and tucking it all in. You can see this happen outdoors, and also to the surface of potting soils in a container. The whole thing tightens and contracts. Then if you were to water this skin, the water just skims and runs right off of it. A slow and steady drip drip drip of rainfall would soften the skin and penetrate, but if it is just a gush and a jolt of water, the plants do not benefit. You have to make pores in the earth and allow the water to soak in.

Thus, you create water holding patterns of soil on the earth. It is that simple; but not often done in planting projects. The process is a bit of extra labor and time and getting dirty, especially if you are working in clay and the stuff sticks all in between the grooves of your boots and smears all over your pants. This way of doing things is nothing novel and if anything it is ancient technology, coming from people who did not have access to irrigation as practiced today. A prime example comes to us from corn farmers of Arizona called the Tohono O’odham who made waffle like soil matrices in the sandy washes where they knew water would gather come late spring and summer monsoons. That way they could harvest a crop of corn in the driest and hottest of climates. In all parts of the world where drip irrigation is not practiced yet, this is how they conserve water and make their plants grow. Furrows. Berms.

Climate, soil. Then it is timing. Ideally you plant around when the rains come. Then you do not have to irrigate and the sky will do it for you. These parts, that is around November December. Usually best to plant after the first rain or two, then the soil is good and wetted and the plants have till March April to grow – spreading roots and hunkering down for the long hot dry period of summer. Remember that around here plants keep growing all winter long. If you look at the hills that go from brown to green that is what is happening. If it was colder then the plants would go dormant, but on the mild coast, plants keep marching on. The sun is a little lower in the sky, there is a bit of a chill, but the plants keep marching on. This is another one of those old timey approaches to gardening and farming – following nature’s rhythm and the seasons. Plant when the timing is right. Not whenever you want it.

Lastly it is the plants. When you plant in a xeriscape style, you want to encourage the plant to establish itself in the local soil and ‘get rooted’. That is what wild plants in nature do. That is how you can survive adverse situations and circumstances. You may want to loosen or remove some of that nursery potting soil that the plant came with. That potting soil is mostly all bark. If there is a hot day and the bark dries out quick, the plant is dead. You dont have to take all the barky peaty soil off, just make sure its mixed up in there with some grains of loam and clay or moist sands. Get the plant roots into the native soil so that as the land dries and that skin contracts and tightens, the plant is a part of that matrix and not something foreign and apart. An alien thing that gets squeezed out and discarded by mother nature.

Other than this basic planting method, it is the selection of plants that makes a xeriscape garden. And how you assemble and combine them together to make a community. Some are low spreading things that cover the earth, others are upright creatures with roots fifty feet deep. They are not separate organisms, they work together to benefit the entire system.

Theres a ton of different kinds of plants to choose from. Many of them are drought tolerant, but more important than being drought tolerant is that you match the site to the needs of the plant. Good fit. Right plant right place like the ol gardeners repeat infinitum. Boy am I a broken record or a MP3 stuck on loop action. Okey dokey until the next group of plants.

The first set of plants we are going to learn in xeriscaping are the succulent and cacti around town. Heres a few handfuls of basic forms to learn. After that you can specialize in the details and be more fussy about nomenclature. If you get these down, then you graduate and can move on to the next group of plants. Here is about 24 plants plus or minus.

Page one and page two are all succulents that are not poky. Well some Aloes have a bit of an edge to them but they are like spines covered with a dob of silicone or lambskin gloves. Cant really hurt ya. Most belong to this family called Crassulaceae which all the biology majors learn about because of their special metabolism. Its like this – most plants work during the day when the sun is out and rest at night. With the crassulaceous ones, with where they live, its too hot to work during the day. So they do some of the work at night, simple like that. Like those mediterraneans who take a little siesta when the sun is beaming, then back to work and dinner at like 10 pm and the merriment lasting long beyond that.

A few members on page one and two are of the Aizoaceae family which when blooming look like the brightest glowing colors the universe can conjure up. Theres also a couple of cactis on these pages but not the typical ones you think of. They are flat pads of non-poky cactus that grow hanging off the foggy wet barky crotches of high mountain trees. Not living in the desert sands or hard scrabble hills. Hey, theres all kinds…

Page three is the poky poke succulent and cacti around here. The poky pokes range from tiny irritating hairs to large thin spines to fine sharp curved fish hooks to a seven gauge sewing needle with a point on it that spells ‘caution’.

The assignment? Study the pictures. Then when we go out for a walkabout you can look for these new friends and try to make an impression. Maybe pick one up to take home, chat about this and that. Cultivate, grow, reproduce, and share with your mates.

These are stressed out Aeoniums, Cotyledon orbiculata, Aloe arborescens, and Agave attenuata in the flower bed out in front of the college by St Francis of the Guns statue by Benny Bufano.

At La Playa Park by Java Beach on Judah and the Muni turnaround, a few of our new friends:

Special thank you to our tour guide and manager of La Playa Park, Anthony Locher!

Introduction to xeriscaping

Dry land gardening

When you talk about the average rainfall per year, San Francisco and Oakland get around 25”, Los Angles around 15”, San Diego less than 12”, Cabo San Lucas in Baja Mexico gets around 9”. Then you start going inland to Death Valley and the desert and you come in at around 2” per year. In drought years it is less everywhere. During those times water starts getting rationed, folks paint their lawns green rather than water them, and all the feral pigs start dying off along with other wildlife. Even three hundred year old oaks and two hundred foot tall eucalyptus go brown.

As you go north in California, the average rainfall comes closer to the USA average of 38” per year. That is about what Santa Rosa and Sebastopol get. By the time you get up to Fort Bragg on the coast or Willits a little inland we are at about 50”, Humboldt about 55”. All that rain falls on the western parts up north. When you go inland towards the high obsidian peaks of Modoc County then we are back down to 14” or less, and 6 8 10 12” in the Great Basin deserts of Nevada.

So that’s nature, we can’t really control where the rain falls, and how many inches of rain and snow fall a year. But once it falls, culture takes over. Dams stop up rivers, make reservoirs, and control flooding. Water works, pipes and pumps can convey that water to farm land and cities. We can move water from water rich areas to water poor areas. Wells can bring the water deep down below the ground back up again for irrigation or consumption. We can treat that water, recycle that water, contaminate that water, waste that water. Use it as we please.

We do recognize that water is a precious resource, and that water is life. Plus, these days, it costs money. It is money. So we try not to be careless with the substance, and hope that everybody gets a share. People and wildlife alike. However, like any limited resource that varies from year to year, theres fightin’ and arguin’ that goes along with the territory.

When we discuss water issues, it gets messy and tied up with politics and morals and country lines and farmers and fishermen and plenty of emotions. Science, which is supposed to be factual and objective and fair, tends to sway and dance, or just throw up its hands and give up. Theres a reason why river riviere riparia rivus rival forms a continuous stream of words. We’ve been fighting about water and life for as long as people have been people.

You’d think that planting flowers and growing trees would somehow be harmonious and be above the fray. But it too is a culturally bound activity with trends, standards, and tight perspectives. So theres a few topics to explore as we ponder xeriscaping – the plants themselves, our attitudes towards them, and how to make our garden a happy place that works according to plan.

Plants evolved from, and are adapted to, the climates and soils of the world, whether that be the sticky humid southern heat of the bayou or the chilly limestone rock outcrop on a north facing slope. They grow best within a given comfort range. Therefore, in your garden, you try to grow the plants that are suitable for the given area. Some plants like more heat, some less. Some plants dont mind the salty coastal winds, while others prefer the calm protected valleys. So on and so forth; plants are like people, they got preferences. Yes you could grow a plant out of its natural zone, but usually you would have to supplement it with artificial means (extra lights, heat, protection). Or, you would have to accept the fact that the plant will not go about its natural life cycle; it will not give fruit, or it might not flower well. Its not happy, not gonna do its thing.

Every culture has got its own look and aesthetic. Of what is desirable and looked up to. And then within that culture, you’ve got a whole lot of variation too. Of course culture being culture, this standard is not fixed, but changes over time. Sometimes that change is enforced externally, whether by violent means or by mandates of the law. Other times it is something that happens within individuals or tribes because the mind opens up to something new and it is a good feeling. You get that why not grin and give it a shot. So this is true for culture as a whole but also for horticulture. Theres a mold, the mold breaks, another form emerges. Like the insects molting, shedding skins, and undergoing metamorphosis.

Fashion is like this too. Sometimes it is rarity that drives desire and demand. Other times it is some charismatic persons who everybody wants to follow. Could be an ad campaign, could be a viral image. Could be some weird kinda ancestral dream you keep wanting to be a part of. Back in the day, after World War II, prosperity was all around. Given the settlers European lineage, what you wanted was a nice big green lawn. Even in the hot deserts of Texas and Arizona and Cali, a nice green lawn. Its not like people were thinking hahaha I’m gonna waste a whole lot of water and enslave myself to this little piece of earth every weekend. Mow it, fertilize it, aerate it, pest control it, water it, dethatch it, and so on. The lawn was a symbol. It was a remnant memory of a green pasture and lovely expanse of hills filled with sheep and milk and cheese and grains. It was an homage to ancient kings and queens and a fighting spirit with knights and armor and axes and yew longbows and the whole thing. It was worth the investment so to speak. Nowadays the lawn as landscaping has spread worldwide. It is a great place to sit and have a picnic, to play on, to take a nap and look up at the sky and clouds. It serves a function, and embodies a story. Everywhere the lawn goes, it takes on another personae. In Guatemala you got the human machete mowing method. Down in the amazon they like – we always cut our grasses short anyways cause we don’t like snakes hiding in the tall grass near the houses. In Asia’s cheap abundant labor pool you got thirty grandmas and grandmas on their knees wearing bamboo hats with asparagus knives picking at every tiniest dinkiest weed in the lawn, all the while mowing with pairs of scissors like they was a haircutter at the salon.

If you have the neat & tidy, everything-in-a-nice-weed-free-row mentality of farm and garden, then some of the native gardens were totally unrecognizable and probably ugly to you. The accounts that come to us from Spanish chronicles of the 1500’s or the 19th century botanists and writers articulates this view. What seemed a messy incongruent jumble of chaos was perfectly orderly to the west coast locals. Diversity was not some flim flam concept for fundraising, it was about survival. The garden included a myriad of plants for food and medicine and fiber and construction. Why would you go weeding something that would provide edible seeds? Why would you throw away the root that would relieve the painful toothache? Just leave it! Granted that they had limited access to metal tools and irrigation. It just wasnt priority or within their capability or part of the cultural mindset to make it just so… controlled. Relaxed is probably the correct word to describe their relationship with nature. They focussed their cultural efforts, organization, and formal structures on the baskets, the sinew bows, the fishing nets, and the coyote stories.

We are at a junction in the garden. The old ideas are still valid, but need to be tempered and balanced with novel solutions for a crowded and conscientious world. That is where xeriscaping comes in. In a sense, the way it is utilized these days, it goes beyond water conservation in the landscape. It dovetails with native plant restoration, designing with hydrozone principles, and the awareness of the importance of water to all life and habitats. It does challenge the old school green estate aesthetic with other ways to appreciate plants and nature. It does so with methods that are slightly less intense and a little easier on the body. Mostly with intelligent and wise plantings. Given that folks do not keep slaves anymore, and not everyone likes the constant din of motorized blowers and hedgers and chainsaws, this is a normal progression. If you could work less, pay less, have more fun, and still look good, why not?! Okay then here we go…

As part of the landscape design class, we visited the San Francisco Botanical Garden to examine the role that water, stone, and plants play as part of the overall design. The gardens feature a diversity of plants from the Mediterranean climates of the world, cloud forests of Central America and Southeast Asia, and temperate zones of mostly Asia, Europe, and North America.

The design of the gardens is a cooperative effort between many different peoples over time. This includes supervisors and managers that stretch back to superintendent John McLaren and more recently folks like Walter Whalen and Matthew Stephens. Notable designers and architects such as Thomas Church, Ron Lutsko, Bernard Trainor, and Roger Raiche have all left their footprints here. Past curators and collectors who have develop the plant palette include Don Mahoney, Bian Tan, Tony Morosco, David Kruse Pickler, and on up to the present day curator Ryan Guillou. Contractors of course play a part in actually placing stones, moving soil, and installing boardwalks. Of late, that has included Rock and Rose and Goodscapes. Lastly, and most importantly, it is the gardeners day to day activities that help to shape the true design of a garden over time.

We will take a counter clockwise tour of the botanical gardens, and check out individual vignettes and specific gardens. Put your critical thinking cap on, and be ready to apply the basic principles we have discussed in class – balance, rhythm, scale, and unity. We may touch upon issues of public and private space, native versus non natives, function and aesthetics, people and wildlife, safety and maintenance. In short, you are called upon to use your skills as a designer to bring it all together.

At the entrance, this is a piece by Guillou. While most of the plants have grown in, and its become a bit harder to discern the pattern, the number of objects is always in odd numbers. Threes, fives, and more. So there is that tension or asymmetry we discussed with regards to repetition of plants and the counter balancing of softscape with hardscape. Count em.

As we traverse the northern edge of the great meadow of lawn, take a look at the planting beds on the right side. The plants are grouped not by geography or rarity or ecology, but by color. All the plants are of the cool blue yellow and white wavelength. In the first picture there is the rhizomatous running grass Leymus condensatus, the yellow feet of kangaroo paws Anigozanthus, yellow flowered Phlomis fruiticosa, and the shrub sticking up is Melaleuca incana the grey honey myrtle. Further on there is blue Ceanothus, gray greenish Echium, and a Griselinia hedge with the variegated yellow borders. All super cooooool.

Go in to the new garden that has been designed by Lutsko and Guillou, it is called the Celebration Garden, a garden meant to be used as an outdoor venue for events. It replaced the demonstration garden; the only remnant of the past here is the pavilion designed by Thomas Church. This garden is also planted primarily based on color – whites, silvers, blues, greens. Elevation wise it is mostly flat and low. The tallest plants planted here are the large fishtail palms Caryota. In time, they are to be overtaken deliberately by the wax palms Ceroxylon. In maybe 40 or 50 years according to the staff.

This garden is defined by wide expanses of turf, followed by silvery Convovulus and low spreading silver Dichondra; tree ferns, silver spear Astelia; blue succulent Senecio madraliscae; blue fescue. You get the idea – color is cool, and the plants range from full sun to shade. The most challenging aspect is likely the litter under the tall Eucalyptus trees, the open and windy exposure, the meticulous nature that is crucial to a rental space, and the safety of 2-4 year olds playing near sharp agaves.

Water is central to a garden. In the old European style it is commonly a fountain in the middle, or in the Moorish style it might run along a trough through the center. San Francisco Botanical Garden is no exception. At the end of the great meadow is this beauty. It is temporarily not running due to construction or repairs. The cinder blocks with the wires on top is a bird deterrent that resembles a daddy long legs spider. It is meant to keep geese and other critters from going in the fountain and pooping there.

Walking over towards the Primitive Garden and you will notice the water trough that conveys water from the Japanese Tea Garden across the street to the large pond known as McBean waterfowl pond. The trough is made recycled materials – specifically it is concrete, aka urbanite. It is lined with a white clay that is called bentonite. A nice thick layer of bentonite will make it water tight and minimize leaks. It is a commonly used material for pond building, an alternative to the thick EPDM rubber liner.

Big ol carp always come by for a hand out at the pond. They are not the fancy pretty koi, they are all gray brown colored. But they are the same fish – a chunky scaly fish with barbels around the mouth that thrives in freshwater that has low oxygen content. It likes a similar habitat as catfish. In many parts of the country the carp is considered an invasive species.

The Australia garden next to the Primitive Garden has a water feature that runs down the middle of it. It is a dry creek bed. This first picture is the end of the dry creek. Over the past ten or fifteen years, all the plants have grown up around this design feature, to the point that it is almost completely obscured by erosion and leafy debris and tall shrubs. But it is still there, the defining cohesive element of the whole design.

Besides water, stone and rock bring character to a garden. Mr Trainor had a neat idea here while making the retaining wall benches and seating. Rather than a smooth level gray concrete of a form, he utilized crumpled up aluminum foil and concrete colorants to create texture and geological age. Yup Australia is a really old continent and so the hardscape seeks to reflect this. I like how as it ages, the grooves and cracks and unevenness picks up the moss and stains of time.

We cruised through the Chilean garden and saw these Andean Wax palms, the tallest palms in the world. Imagine the Celebration Garden when the palms grow up tall! Well I’ll probably be dead by then but it is worth dreaming about…

The Zellerbach Garden is a formal garden that is high maintenance. To look good the perennials need a lot of attention. Luckily it has some help from a group of volunteers who have been coming for over thirty years weekly. Deadheading, pruning, weeding, and so on. It is another garden that is not focused on diversity and ecology, its palette is based around the pinks and purples, with a smattering of red white and blue. So it is warmer in temperature and wavelength. There is a little bit of symmetry – the matching structures and trees – but it also has that English perennial border feel of happy exuberance and abundance. Notice how the perennials are for the most part herbaceous, not woody. Hence over time you get nice clumps of blooms, and not huge shrubs trying to take over and shade out everybody else.

When you line yourself up under the gazebo, and look back at the expanse of the botanical garden, you will see the axis of view that defines the formal gardens inspired by European royalty. Ideally, you would be able to see clear across to the other side of the garden, with the water feature in the middle. Can you see the white rim of the fountain?

Back to water – the water trickling down the stones of the Moon viewing Garden. This water feature is constructed in an old fashioned manner – lined with concrete, with round river rocks pressed into it. It is the same method of construction as the ponds in the Japanese Tea Garden. On this day, the upper waterfall had water, but the lower troughs leading to the moon viewing pond was dry.

The deck and view of the pond was closed for a wedding. So sorry – could not get in to show you the sights. The pond there is shallow, and there are no fish in it. It is a raccoon hunting ground. What is a neat feature there is a small island in the pond that is in the shape of a turtle. And the overhanging Coriaria tree is quite a specimen too.

There was more closed area by the Conifer Lawn. Signs explain that a coyote had been sighted and perhaps threatening a garden visitor. This was the area that it was last seen in. What a drag. Between Covid and now the coyote.

Finally at the top of the hill is the succulent and cactus garden. The placement of this garden took into account the ecological needs of this group of plants. They like it hot, with good drainage. The monastery stones used for the retaining walls have great thermal mass, and radiate the heat they have stored during the day, at night. There is a diversity of forms and colors here, they are united by the predominantly dry and desert like conditions of their native habitats – whether that be Africa or the Americas.

Back to water again as we go down the hill through the grove of coastal redwoods. It is running dry here as well, whereas in the recent past stands of skunk cabbage wet their roots here under the Sequoia canopies alongside ground covers of redwood ginger and redwood sorrel.

Water always descends to a low point. The lowest point in the botanical garden is by the Arthur Menzies Native plant garden and the old greenhouse. The water ends up in a big reservoir where a pump in a pump house, staffed by a stationary engineer, pushes the water back up the hill.

The main body of the California native plant garden is in the shape of a large oval, with a small pond and a bridge at the head of it, and a dry creek that runs through the garden. (This is a common motif, no?). Here we are looking from the end, or the base of the garden, up at the head. The asphalt road that cuts across it is a new addition – meant for easier access for supplies to the to-be-built new nursery. At the end of the dry creek is a tiny tule and cattail lined pond and an Alder tree, which is commonly found close to water in nature.

Alongside the new road are new plantings. On the far side are woody shrubs – sticky monkey flower, toyon, coyote bush, coffee berry. The dominant shrubs of the coastal sage scrub. On the side closer to the rest of the garden are low plants more commonly found on the beaches and sand dunes – beach sage and beach strawberry, plus some coyote mint of the clay rocky uplands too.

The original design plan of the native plant garden was to showcase the vegetation communities of California. The palette is an ecological one. There was the native bunch grass meadow that was common in central valley. There was the coastal scrub and chaparral of woody shrubs all knit together. There was the oak studded foothills and woodlands full of acorns. There was the serpentine outcrops of rocks and gravel and strange endemics. And there was the riparian riverine plants alongside small drainages and lakes. There was no desert biome represented, neither the low Anza Borrego desert flora nor the high Mojave desert flora.

The bunchgrass meadow has been painstakingly planted. Heres Purple needle grass Nasella pulchra, tufted hairgrass Deschampsia cespitosa, and California oat grass Danthonia californica. You can still find these plants occurring naturally in San Francisco. Nasella and Danthonia form small stands at McLaren Park in the grasslands by Gleneagles Golf Course. They are periodically burned around the Fourth of July. The only place you will find wild tufted hairgrass in San Francisco is on Bayview Hill by Candlestick. It is in a few patches where it is wet and close to the groundwater seeps near the top of the hill. It is scattered and does not form dense masses.

The chaparral is often dominated by manzanitas, yerba santas, chamise, and sagebrush. In the native plant garden the manzanitas have been heavily pruned to accentuate their branches and open up the views.

Okay. We are still following water, up the hill, past the California natives, up into the temperate Asia section of magnolias and dwarf conifers. There are four distinct ponds, all connected to one another by pipes and gravity. Simple and elegant design. The bottommost pond was dry, a pond that originally housed carnivorous plants. The rest had water. These ponds are also lined with bentonite clay. Occasionally leaks will occur at the edges where raccoon and coyote and skunk hunt for crayfish. Then the gardener has to fix the leaks… The ponds have names like bamboo pond, dwarf conifer pond, and Annelli Pond.

At the end of the tour we ended up back at the entrance, by the library courtyard garden, a garden enclosed by the Spanish monastery stones. With, you guessed it, a small fountain in the middle. There is a good history of the stones here:

Unlike a regular building material you go and buy at the store, the stones came in irregular sizes and shapes. So as a designer, there really is no way you can draw a plan and say make it look exactly like this. You can come up with a preliminary idea/structure, and then just let the stone workers run with it. It is in a sense off the books, improvised, and built in an organic manner. This is the same approach we use when building with recycled materials like granite curbstones or granite scraps from the cemetery dumpster.

Not sure about who did the work on this wall, but for a similar structure by the rhododendrons, they had to bring in four or five old time stone cutters from Oaxaca Mexico to put it together. This is not a common trade around these parts anymore, more like traditional artesanal craft. Pretty neat results.

The fountain was dry. And the plantings? They are new. Another design by the current curator all in purple with a touch of orange from the Alstroemerias. A plant palette based around, for the most part, one color.

Well we will end the tour with a picture of plants wild collected from southern Spain – snapdragons, red poppies, yellow rockrose, esparto grass, and asparagus. A plant palette that come from a place, a community, an ecological niche, and a climate similar to our own. Well, enjoy, and see you in the gardens!

Water management addendum:


As gardeners and horticulturists, we talk about salts the way the chemists do
we are talking about a crystalline solid formed by a positive and a negative ion

table salt is sodium chloride, nice clear white crystals sitting in a shaker jar
pour that salt into water and the bonds split
the salt dissolves into solution
sodium and chloride become ions swishing and swashing around,
tucked within the H2O
sodium ion is charge positive +
chloride ion is charge negative –

an ion, by the way, is an electrically charged particle
the particle can consist of just one atom,
or it can consist of a group of atoms – polyatomic, a molecule
for example, sodium chloride is one atom of sodium to one atom of chloride
if the salt was ammonium nitrate, that would be one ion of ammonium and one ion of nitrate
ammonium is NH4 (one nitrogen and four hydrogens)
while nitrate is NO3 (one nitrogen and 3 oxygens)

we can now call that water solution full of ions an electrolyte,
meaning it conducts electricity
kinda the same concept as a car battery
or the special vitamin water or sports drink that says it replenishes your electrolytes
or the cells in your body with sodium and potassium coming in and out all the time
we are all skin bags of water, filled with bits of charged ions

now go look on any fertilizer or potting mix label

ammonium nitrate salt
ammonium ion is positive, nitrate is negative, easy

potassium phosphate salt
Potassium is positive, phosphate is negative, easy

calcium nitrate salt
calcium is positive, nitrate is negative, easy

potassium sulfate salt
potassium is positive, sulfate is negative, easy

all those -ates: sulfate nitrate phosphate
theres gotta be a pattern
yeah it just means theres some oxygen in there cause oxygen loves to bind with others
sulfur and oxygen – sulfate
nitrogen and oxygen – nitrate
phosphorus and oxygen – phosphate

if you are ground water running through limestone channels or quarries
for sure you will pick up some of that calcium and magnesium in the limestone
then that water is called ‘hard’, and it forms deposits on the kettles and things called ‘scale’

if you are ground water running through sodium rich soils
then you will pick that up too
and become sodic or saline or salty
maybe somebody will put you in a pond, and evaporate the water
then bag that salt and sell it to passerbys and traveling caravans

if you are rain water, that is pretty pure stuff for the most part
unless you picked up some burnt stuff particles on the way down from the clouds
some bits of sulfur or nitrogen from the volcano or the power plant…

in general
as a gardener and nursery person, you want minimize the salt buildup in the soil
a little bit of salts (fertilizers) is good right?
yes, but you want a balance, you want just enough, not too much of a good thing
which becomes a bad thing

imagine you have the soil chock full of sodium ions
and the plant stops absorbing the other ions altogether
no more magnesium and calcium and iron and copper and potassium and zinc
all it gets is sodium
not good, gonna get sick
plant goes caput, and your career as a grower goes down down down

time to time you may have to leach the soil, or add other things to compensate & balance for
the distribution and quantity of ions
the amount of salts

last thing
just to be technical and make the high school chemistry teachers happy
a negative ion is called an anion
and a positive ion is called a cation, a ca+ion