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In the cold and dreary months, neophyte gardeners throughout the world arm themselves with graph paper, sharp pencils and good intentions. Surrounded by seed catalogs from Jungs, Gurney’s, Baker Creek Heirloom Seeds and their regional equivalents in any of dozens of languages*, they pore over the sunlight and soil and moisture requirements for hundreds of unfamiliar vegetables. Who knew there were so many kinds of carrots? And the garlic should already be in the ground? Oh, no!
Undeterred, they forge ahead with visions of grilled corn on the cob just minutes from the stalk and tall glasses of chilled tomato juice savored in relaxing moments as the fireflies light up the patio and good friends are close at hand wafting through their minds. Possibly that glass of juice has been transformed into a Bloody Mary with a shot or two of vodka, some cracked pepper and a slice of lime pressed over its rim. It doesn’t matter … it’s all good.
Then, like their predecessors of the past two centuries, since the day that seeds became a mail-order business, they run into a totally intractable problem.
Which parts of their property get enough sunlight for a garden? Short of demolishing the neighbor’s garage and moving the house closer to the street, where can a gardener find a bit of soil that the sun can also find?
Well, not to fret, there’s an easy way to find out. Pick a clear winter night with a bright moon. In the northern latitudes, choose a date between December 1 and January 1 and go out to your proposed site at roughly midnight with your measuring tools. This also works for the southern latitudes, except that the dates would be between May 1 and June 1.
The moonlight will be shining at midnight roughly where the sun will be shining at noon, six months later. You will be able to see which areas of your garden will get enough sun (six or more hours – preferably much more – for most vegetables) and which will not.
Don’t forget to mentally ‘add’ foliage to any tree or bush shadows. The outline of the limbs count as a shaded area. This is also useful information as it tells you where to put your seating or maybe even your compost pile if you have a shady spot toward the rear of the garden.
Take your measurements, then come inside to warm up again before laying down for the night. In the morning, you can start planting your garden … on paper.
The further north or south of the equator you are, the more important it is to take every advantage you can of the reduced sun you get. Closer to the equator, shade might be the premium quality that allows you to grow more tender varieties away from the worst of the heat.
With pencil and paper in hand, consider that any pronounced change in elevation of more than just a few feet (~1 meter )will contribute to micro-climates within the garden. Water and cooler air both flow downhill. The lower soil will tend to remain moist and cooler for longer and might be your best location for lettuces and peas. The lettuces can go in as soon as the soil can be worked. The peas should wait just a little while longer so that warmer soil will cause them to sprout before they can rot. A bit further up the slope, plant bush beans and again, interplant them with lettuces. Lettuces need a generous amount of nitrogen and the beans and peas will, through structures on their roots known as rhizomes, capture more nitrogen from the air than they can use and release the excess into the surrounding soil. If interplanted closely enough, they will also provide some cooling shade for the lettuces and thus prolong the harvest. When spinach and lettuces get hot, they ‘bolt’. That is, they grow bitter and turn to the serious business of setting seed. If you’ve planted heirloom varieties (a practice I recommend) it’s a good idea to permit a few plants to complete this cycle so that you can harvest mature seed for the following year.
As you move up the slope, plant things that want increased levels of heat, such as peppers, corn, bush (determinate) tomatoes and squash. At the top of the slope, plant indeterminate tomatoes and pole beans on trellises. They both love heat and are both susceptible to various strains of mildew. They will thus benefit from the increased exposure to the sun and the wind, which will tend to keep leaf surfaces drier. Also, by planting them at the top of the hill, the shade they might cast on the rest of the garden is minimized.
If your plot is generally level, but bordered by structures and trees, try to plant the heat lovers near the sun-facing side of the structures. This will help trap heat and greatly accelerate their growth (if they have access to sufficient water in the soil). You can magnify this effect by painting the sun-facing side of the structure white, thus reflecting much of the solar energy that the structure would have absorbed back onto the plants. Try to plant the cool-loving plants in areas that will become shady as the season progresses and trees and bushes begin to leaf out. Do not plant the heat loving plants on the side of structures away from the sun. There they will receive neither enough light, enough warmth or enough ventilation. They will likely yield poorly, if at all, before succumbing to diseases.
Bear in mind that the trellises for climbing plants such as beans, peas, squashes, tomatoes and grapes provide areas of filtered sun and reduced temperatures for continued crops of leaf type lettuces such as arugula, spinach and Black-seeded Simpson and the loose head varieties such as Buttercrunch or Chadwick’s Rodan.
Planning your garden can be just the start of many enjoyable days in it. Your pleasure, and its productivity, will be greatly enhanced if you give proper consideration to the needs of your plants when choosing a site for your garden.
– Bill
*Baker Creek offers seeds from Africa, Japan, Peru, Siberia, Europe and the US. Oh, and their free, lushly illustrated and well-written paper catalog is technically “seed porn”. You’ll find them at www.rareseeds.com.
