January is a peculiar time in California. We can have brilliant, cold days that draw us outside or tremendous rain storms that force us indoors. For gardeners, winter is generally a slow time, a time when we observe the shapes of the trees once the leaves have fallen, wonder what will come up in the perennial bed or muse over a new garden space for spring.
In fact, planning a new garden is an excellent use of the winter gardening lull. Perhaps there is a patch that needs renovation or you are interested in trying a new type of garden, such as a habitat garden for birds and butterflies or a mixed ornamental and edible garden. With some care in planning, you can be ready to go when the season changes.
There are several logical steps to take in planning a garden. First, of course, is choosing the site. You should consider the use of the space: Is it to provide a charming view from your kitchen window? Does it surround and beautify a patio where the family gathers outdoors? Will it provide delicious fresh vegetables for the coming year? A general overview of the site including its size, location, use and general topography is a good place to start. Is the area on a hillside, or is it level?
You can draw a simple sketch showing the general layout and dimensions of the space. Note any buildings, areas that you may want to screen, or extant plants or features in the site.
Once you have your sketch, determine the general climate in your area. Sunset garden books use a zone system based on weather patterns. Most of Marin falls into zones 15, 16 or 17. The USDA also has a system of plant hardiness zones, locally generally 10a or 10b. You can determine your zone number by going to the website and typing in your ZIP code. (planthardiness.ars.usda.gov/PHZMWeb/) Notate these numbers on your sketch for easy reference.
Next, you need to determine the microclimates that occur in your garden site. Watch the pattern of sun and shade throughout the day. Winter is the season that provides the fewest hours of light coming in from a low southern sun.
Note the pattern of sunlight and shade on your sketch so you will know whether to plant sun-loving or shade-loving plants in that area. Recognize other things that might affect your garden, such as a low-hanging eave that protects against frost or a deciduous tree that will be leafy and throwing shade in summer.
It is a good idea to get an idea of the quality of your soil. A simple soil test kit from your local hardware or garden store will allow you to test the pH (acidity or alkalinity) in your garden soil. Check the texture by holding a clump of the soil and seeing if it is thick and claylike or loamy and breaks apart easily or if it is somewhere in between. Soil amendments such as compost can be added to improve the composition of your soil. It is a good idea to know at least generally what type of soil you are dealing with.
Now comes the fun part: choosing the plants. One way to start is by choosing a color palette. You can apply basic principles of color theory to gardens just as you would to home design or other artistic projects.
If you want the colors to pop, choose plants with flowers or leaves from the opposite side of the color wheel — complementary colors like blue and orange or violet and yellow. You also can create color harmony by choosing analogous colors — colors that are next to each other on the color wheel like yellow, orange and red.
There are many plant books that list plants by color to assist you in finding plants with just the right shades. Draw up a preliminary plant list of plants you like, that are the right size when grown and that will fulfill your garden vision.
In addition to color theory, you can apply basic design principles to gardens. Some considerations include scale (take care with how large the plant will be when fully grown), balance (creating a focal point and balancing visual weight on either side of it) and perspective (for instance, using bright materials at the front of a bed and grayer or more neutral colors toward the back can expand the space). Look at gardens you enjoy and see how the designers have used these principles to create the feeling that you like.
The final consideration in plant placement is irrigation. If you group the plants within your garden by water needs — called hydrozoning — your irrigation will be more efficient and the plants will be better served.
Planning your garden in winter is a lovely way to dream of spring.