Polyculture is the practice of planting a community of interrelated, interdependent plants, mimicking in your garden (in our case a raised vegetable bed) the complex relationships that are found between plants in nature.
In the case of food crops, a polyculture tries to set up conditions where you can eat almost continually out of a garden bed filled with different varieties of plants maturing at different times. The faster growing plants protect the tender ones from the sun. The thickness of the planting virtually eliminates weeds, and also functions as a living mulch, keeping the soil moist and cool beneath a carpet of green. These beds look quite different than the tidy rows of carrots and cabbages one sees … well, one does not see vegetable gardens anywhere if one lives in LA. One remembers them from illustrations in Peter Rabbit.
Okay, you want specifics? Here is an example of a professional polyculture bed out of Gaia’s Garden, one which creates salads, cabbages, and beans. It is written for people who live places with cold winters (as are most gardening books, alas). So Angelinos wanting to follow his plan can start this earlier, perhaps in March. The SurviveLA polyculture that will be described after was started in October.
Polyculture from Gaia’s Garden, attributed to Ianto Evan:
After the last frost cover your garden bed evenly with a light broadcasting of the following seeds. Don’t mix them before broadcasting because they will fall differently according to their weight., and so separate out in the throwing. Spread one type of seed at a time, aiming for an even distribution of each type of seed all over the bed. Sow: radish, dill, parsnip, calendula and many types of lettuces, late and early harvesting types to extend the length of your season. Cover the seeds with 1/4 inch of soil.
Meanwhile, start cabbages from seeds in containers, early and late maturing varieties.
4 weeks after sowing you can pull some of the first radishes, because they grow fast. As you eat those, put the cabbage seedlings in the holes.
6 weeks after sowing you can eat the lettuce. First as a baby lettuce mix, later in its more mature leafing form. Pull out entire plants to make space, so things don’t get too crowded.
Continue this way until the soil warms up. As you eliminate lettuce plants, begin to put bush beans in their place. The dill and calendula will start coming into their own, and the early cabbages. The beans will be ready by midsummer, and the parsnips and the rest of the cabbages will follow in the fall.
So you see, the secret is in choosing plants with staggered harvesting times, so they don’t come in all at once, overwhelming you and competing with each other for space, and also in choosing plants that are not all from the same families, so they don’t compete for the same nutrients. The beans in the polyculture above help replenish the nitrogen in the soil that the other plants drain out. Very clever. With little effort compared to normal gardening, you will be harvesting veggies from one plot all year long.
SurviveLA’s Impetuous Salad Bed
Now the SurviveLA bed is not so well organized, because we don’t know as much as these permaculture folks, but it has been very successful so far, meaning no pests, no weeds, low watering, and tons of salad.
This bed was started in October, as soon as the weather had decidedly shifted toward the cool. In LA, it makes sense to grow tender salad greens and the like in the winter, when the the sun is low, the climate is gentle, and our only rains fall. Lettuce loves that kind of thing, and hates hot sun. If you plant lettuce in LA in the summer you are in for a world of sorrow.
As above, we broadcast the following seeds evenly over our 4′ x 8′ foot raised garden bed. It is set up with fancy new drip emitters for lazy watering. In the past, we’ve watered this bed with the more casual but quite functional soaker hose. Both are preferable to standing around with a garden hose, and the plants like it a lot better too. FYI, plants prefer occasional deep soakings to brief daily showers. However, while the seeds were sprouting and delicate we did water from above with a hose set on gentle sprinkle.
Not knowing all of the habits of these plants, many of which are from growitalian.com, we just threw them all in to see what would happen. When the coldest nights are over in a couple of months we will plants some beans, as above, for nitrogen fixing. For now, these things are growing in a riotous mix:
Wild fennel (non-bulbing variety)
Lettuce mix (various types in one package)
Rapa da Foglia (leaf turnip)
We’ve been eating all of it in its infant form, except the radishes, which have markedly hairy leaves that you don’t want in your salad. Just lately the leafy plants have become easily distinguishable from one another, and are taking on their full flavor. To keep up with the thinning which is necessary at this stage SurviveLA must eat at least one salad a day. But it is no hardship to eat greens so fresh and tender–once you grow your own salad, you will feel cheated each time you have to eat salad from a bag.
In the photo you will see how tight the planting is in the bed. It is perhaps a tad too tight. We are eating as fast as we can, pulling whole plants for the most part, shooting for the ideal of giving each remaining lettuce and chicory a space about the diameter of a cereal bowl for itself.
When the lettuces are full grown, you can harvest leaves off the individual plants instead of harvesting the whole plant, thus just five or six mature lettuce plants can provide salad for two people a few times a week, leaving lots more room for other plants. Beans will come in the spring, and also some yet to be decided crops which we can expect will do well in the heat of early summer.