In the end, maybe it doesn’t matter at all. What plants you choose and where you plant them. Plants are beautiful, they are all beautiful. Even the ones with the teeny rinky dinky flowers, even the ones with the careless sprawling habits, even the ones with the stinky carrion scented flowers. Plus, isn’t beauty in the eye of the beholder? So then how do we evaluate the ‘correct’ grouping and layout of plants in a garden? Okay, we are going to put beauty aside, and leave each person’s aesthetic choices to themselves. Instead, we are going to focus on factors that are more easily quantifiable and comparable. And afterwards, look at a few scenes around town, and encounter some challenge questions.
Criteria:
Water use. Like all things in nature, plant distribution is often cyclical. With regards to human society, it is also trend and fashion based. In a hot and dry landscape such as central and southern California, the wild plants get by with about 15”-20” of water a year. Gardens, thats another story. In the rush after large scale water works projects like big dams and thousand mile long aqueducts, people are happy to show off their new found control and utilize some that liquid impounded in the reservoirs. So then deserts of big basin sage and juniper turn to flat green lawns that guzzle and suck. Annual, ephemeral meadows of lupines and phacelias that bloom because of winter rains – those places become transformed into a four month long celebration of english perennials and the likes of gladiolus and roses, with the irrigation coming on everyday at 5 am for fifteen minutes.
This goes on for a while, until the drought hits, or the general consensus turns against wastefulness and creating too much illusion in the face of stark reality. The water bills go way up and rationing starts. Then, the lawns start to get switched out for dry land succulents; xeriscape style gardens of the Rocky Mountain plateaus become in vogue; on the front page of design magazines are plants adapted to an environment with water in short supply. So economics, status, and emotions all help to dictate the palette of plantings.
Granted, there are always kind folks holding down the fort of the idyllic eternal spring landscape. Folks who don’t mind paying for water no matter how exorbitant the cost. Folks that aren’t going to start playing golf on a course made of gravel and plastic turf. There is just something about that criss crossed fresh mowed lawn on the outfield of the baseball field. These folks are great clients, and can really help your career along. You may also have clients who are a little more mindful of their wallets, or what their neighbors are saying. Maybe a little bit more common sensical with regards to water use. So design a smaller lawn, or suggest a hillside of thick perennial grasses and sedges filled with poppies. Plant more plants from the mediterranean climate that is seasonally dry like ours, rather than plants from a temperate climate with abundant rainfall.
In and of itself, there is no right or wrong with relation to the use of water. In general, if there is a lot of it, use it! If there is not so much, take it easy! Balance. What is important is that you give each plant the correct amount of water for its health and well being. If a plant is accustomed to high montane slopes and seasonal dryness, it can suffer from too much water – often the result of being planted in a spot with poor drainage, or irrigation gone awry. This poor plant would then have trouble breathing, get root rot, go brown and die. This is what you want to avoid. Sick plants, dead plants.
Sun and Shade. Okay, look at a yard or a garden. Now watch the sun move overhead. Watch the sun for a whole year as it passes over and through the garden. Where is the sunniest spot? Where is it shady? In the far corner? Next to the house? Does the neighbor’s huge tree block all of your sunlight? What about the new addition they did without pulling the permits?
Now go hiking. On a southern slope, what are the plants growing there? Go to the north slope, underneath the trees, or along a wet drainage, what plants are growing there? If you do enough of this kind of exercise, you will notice that plants have preferences for particular sun exposures, and have spent thousands of years becoming comfortable in those situations. Some plants are ‘generalist’ or ‘not picky’ or ‘easy’ and ‘adaptable’. They seem to grow well no matter what the kind of bungling mistakes you make with regards to sun or shade. Others are not so tolerant and flexible with regards to their comfort zones. If you plant them in the wrong place, They suffer burn marks, they look sad and wilty and floppy. They just sit there and don’t grow at all, or they become pockmarked with fungal spots and covered with hard shells of scale. They are like ‘just kill me already’, but around here theres no winter cold snap to take them out of their misery. And, they look just hopeful enough that you are like ‘well I’ll give you another chance’…
If you want to plant a fruit tree – a tree whose fruits ripen because of the sun. Where do you plant it? In the sunny or the shady spot? Do you space it out so that it gets plenty of sun? Or do you cram a bunch of em in there because you think ‘more trees, more fruits, yeah!’? This is a basic criteria, but often neglected. The amount of light, it makes a big difference! And the awkward microclimates of any yard, especially in San Francisco, makes a difference!
Wind and air. On the coast, it is windy. Mostly windy in the summer, in the afternoons. But in the spring also, and the winter too. Fall the wind occasionally goes offshore, blowing from inland out to the sea. Otherwise, it is onshore.
When they established Golden Gate Park in San Francisco, the engineers and architects and planners knew they had to contend with the wind. And the sandy soil. You cannot stop the wind. We have really good technology, but we cannot stop the wind. I am sure somebody is working on it. Harnessing it for energy and such. But until then…To avoid wind tunnels, park creators established winding roads and pathways. To break the wind – plants. But what kind of a plant could tolerate such howling conditions? A plant from the coast, or a plant from the stillness of inland plains? A perennial shrub, or a bunch of annuals that wither in months? A plant with tiny waxy leaves, resistant to dessication, or a plant with juicy big leaves constantly demanding more more more more moisture?
Wind dries everything. It dries the soil, it blows the water right outa plants. It tears up the leaves, and can be, well, annoying. If a plant is used to the wind, like the Pelargoniums of Africa or tea trees of Australia, they just chug along and do their business like usual. They be bloomin, singin, laughing like those 20 knot gusts are no big deal at all. Now, if you are usually happy in a calm woodland setting, and not used to the wind, like for example a kousa dogwood, then you are hunkered down and trying to survive. Doin nothin. Even if you have enough water. Even if you have all the nutrients you need. No flowers, no fruits, no nothing. Just catatonic zombie waiting. Waiting, holding out. Hoping it will stop one day. The wind.
Too little wind, like in tight corner with no flow. Or an over planted sheltered garden with buildings on all sides – that can cause problems too. Imagine you are in a 10’ x 10’ room, cant move, with twenty other people. Bugs are gonna take notice, disease is gonna set in, and a cough or a sneeze is gonna cause problems for everybody. A little ventilation, a window, a fan, a little more space for everybody. That is good plant health for long term designs.
Soils. By now you might be somewhat disturbed or curious. Wow! There is so much to figure out with regards to proper plant selection and placement! Its so complicated! But wait… There’s more! Get out the shovel and start digging. Not just one spot, not just five inches deep cause you hit a hard spot. Go deeper, try different spots. Wet it, squeeze it, check the drainage. Get a soil test. What do you have? Maybe a cart load of lead and cadminum? Now theres a consideration if you are planning an edible veggie garden. All sand with no nutrients? Well those apples and plums are gonna need some amendments and fertilizers. The soil test says tons of cation exchange capacity? That could be good or bad, depending if you want an orchard or a whole collection of Australian plants that prefer poor soils. So no, you cannot just plop any plant anywhere and make it work. Unless you are sticking to the new zealand flax, agapanthus, and rosemary. The ten easy plants you see in the gas station islands and shopping mall parking lots. Then, take into account the interaction between water and soils and plants… Did you know that our oaks like to have a bit of summer dryness in the roots, so don’t plant a lawn all around it? Or that the plants they are using in rain gardens are from the perennial wet zones, not seasonally wet zones, and are not actually appropriately planted? Even though they are natives? Just cause you were here five hundred years ago does not mean you are adapted to every single site. You got preferences just like any plant.
Maintenance and time. Here’s one that makes a lot of sense, but gets forgotten always. For most gardeners and arborists: it is easy and fun to cut branches off a tree, time consuming and tedious to pick it all up and haul it away. It is a joy to cook and eat, not so much to bus and wash the dishes put everything away. In the garden, many designers have a great knack for the install and first couple of years, but it tapers off real quick after that. The lack of thought and consistency for maintenance is the fate of many a landscape.
Again, the key is a balance. You can be picky to the point of madness in the garden. Remember, this is mother nature we are talking about. You are not in control! This is not a war or a competition. It is more like a dance back and forth. Try to see the big picture and enjoy the sunset and birds chirping. On the other hand you do not want to be sloppy and unkempt and derelict in your gardening duties to the point of neglect either. Somewhere in between.
There are high maintenance gardens that require frequent daily to weekly attention. Golf greens, corporate lawn, fine tuned english perennial garden, European formal garden, the edible vegetable garden. A couple of weeks of workers calling in sick and these places will start to show the overgrown edges and weeds popping up. It goes downhill fast if nobody is on it. These gardens in general require labor, machines, and chemicals. Thats what it takes. High maintenance. Neat and crisp, but on edge, not relaxed.
There are medium maintenance gardens that require weekly to monthly attention. This could be a garden with some long hedges or an ivy covered wall. A garden with rhododendrons that require deadheading, some orchids that need to be repotted, and sages that have to be cut back when they get too big. An irrigation system that has to be flushed and cleaned and run, leaves from the deciduous trees that have to be raked up and bagged. So some work has to be done. Not all the time, but once in a while.
There are low maintenance gardens that require monthly to quarterly to biyearly to yearly attention. They just need a trim and a sweep every so often. They are either densely planted like a wild area, or sparsely planted but smartly mulched. The plants dont need much water, or pruning, or fertilizers, just a touch here and there. If you fall asleep and wake up three months later, its okay. The garden more or less takes care of itself and still looks pretty good all the same. Plants are probably a mix of native and non natives, chosen for their hardiness and ecological fitness for the site.
There is no zero maintenance gardens. Gardens are work! If you want zero maintenance concrete is the answer.
Well that’s most of the measurable criteria that we can use when selecting and placing plants. Besides these factors, we also base wise plant choice on the prevalent diseases in an area and the susceptibility of the plant to that disease. Growth rate and spacing is another consideration. As is diversity and ecology as relates to birds, butterflies, amphibians and reptiles and the like. Well we will talk more about those another day…
Water use is measured in gallons, or in inches of precipitation (one inch of rain is about 623 gallons per 1,000 square feet). Light is measured in its brightness (lumens), its duration (hours), and in its spectrum (Infrared to UV and everything in between and beyond). Wind and air is measured in miles per hour or knots, and the direction is always taken into account. Temperature is in there too somewhere between sun and shade and wind chill. Soil tests take into account the amount of clay, silt, and sand; the amount of ions present such as nitrogen, phosphorus, potassium, iron, lead, chloride, etc. The tests also measure pH, the amount of organic matter, cation ion exchange capacity. The soils will give a clue to the drainage of a site, and indicate whether amendment is needed. So listen to the earth. Finally, there is maintenance. There is a wide range when discussing all facets of gardening. In general, the more complicated and diverse a plant palette, the more knowledgeable is the gardener. So in a botanical garden, or a primary rainforest, the gardener is at the level of a PhD botanist – ten twenty years before you know all the plants and their culture, before you are proficient in your job. For example, in San Francisco Botanical Garden, back in its heyday, a gardener’s beat would entail caring for two thousand distinct, somewhat uncommon to rare species, in a six or seven acre area. A rare species is like the only plant of its species of its kind in say a three or five six hundred mile radius. In contrast, the basics of mowing a lawn well and edging it, that you can learn to do in a few days. Its the subtle nuances of a terrain that takes many more years to figure out.
In general, the more legit, the more professional, the newer the truck, the more expensive is the gardener. However unlike workshop tools, in gardening, fees and cost are not necessary indicative of quality. That is to say, sometimes there is some super nice humble happy gardener university trained or life trained horticulturist who is charging only $25 an hour for the best most amazing work. While in the same city a fancy smooth talking gardener who doesn’t know what they are doing is getting $90 an hour for poor quality work. If all gardens were exactly the same, and there was only one way of doing things, we could standardize the work. But gardens are distinct, and every place is different from the next.
In a high maintenance garden weeds are a constant concern, due to their fast growth and prolific nature. Unless you have a crew of gardeners working non stop, you will not be able to keep up. Therefore, many places will resort to the use of chemicals. If done legally signs are posted, proper safety gear is used, people are trained and proficient. More often than not, spraying is done after hours or illegally, so keep an eye out for a patch of green that suddenly turns yellow. And do not pick the edible weeds that are growing in such places. Then, if we are going to play the blame game, whose fault is it? The worker on the ground trying to hold it together, making the place neat and tidy? The middle management supervisor under pressure to perform more than is humanly possible and turning a blind eye? The unrealistic expectations and lack of connection to nature on the part of the boss? Or the overall vision of how we work and relate to the earth herself? This is a bigger discussion than fits here…Forget playing games, just get your shovels out and go to work!
Here are a few pictures from a town walkabout. Take a close look. Using what we just discussed here, try to interpret the scene – the relationship between the plants depicted and the water, soil, sunlight, air, and maintenance over time. I will give you a fair amount of information about the first scene. Give you a little bit of information about the second scene. And give you almost no information about the third scene.
Choose one of the three scenes, and write a couple of paragraphs describing what is happening. Also, answer these questions as they pertain to the picture –
Do you like this garden design? Is it something you would do?
How would you change or improve the design or the maintenance of this garden?
Okay here we go. Remember, only pick one scene to write about. (A), (B), or (C).
(A) Okay a few clues and hints. The soil is clay. This garden sits on a curvy wind tunnel of a street on the shady side of the street. Plants are Agave on the left, barrel cactus in front, Euphorbia maybe ingens on the right, and another cactus in the back I’d have to ask a cactus person, cereusly? You dont know it? 
(B) This site is a south facing hillside in a clay soil. Irrigated by rotary pop up sprinklers. You will have to figure out what the plants are, and your opinion about them.
(C) The plant is a plant of the Cali coast called sea thrift or Armeria maritima. Usually in nature it is pink not white flowers.
Mission Azul 