Saturday, February 9, 2013

Plant Guilds for the Vegetable Garden

Now that it is February, it is time for me to do more than just peruse the seed catalogs: it is time to formulate a garden plan! That means it is time to create this year's plant guilds. This method is also called companion planting. Companion planting is using plants that provide nutrients or services for each other that generate a plant synergy, allowing one or both of the plants to grow better than they would without the other.

Getting Ideas

For me, the best way to get new ideas about plants that might work together as companions is to read up on what others have tried. This includes forums and other blogs. I also check my bookshelf to see what is helpful. Naturally, I reviewed my copy of the classic Carrots Love Tomatoes by Louise Riotte. Louise also wrote a second companion planing book, Roses Love Garlic. Another good volume for help to companion planting is Sally Jean Cunningham's Great Garden Companions. While Louise Riotte focuses entirely on plants in her books, Sally Jean Cunningham includes information about garden bugs, good garden layout and design, and many other tidbits that can make a difference for the novice, or even experienced, gardener.

Making Your Own

There are several roles for which a plant could be considered as a worthy companion plant and guild member. Some of these are:
  1. Nutrient accumulator / nitrogen fixer - These plants naturally provide in-the-ground fertilizer for others nearby. One type forms a symbiotic relationship with bacteria that allows for nitrogen to be taken from the air and put into the ground around the roots. Legumes, such as beans and peas, are examples of this type of plant. Another type I affectionately call miners. They push tap roots deep into the ground to pull up trace elements and other minerals. The much maligned Dandelion falls into that group. See my post on nutrient accumulators.
  2. Insectary - These plants provide easy food for many insects, thus quickly attracting a large variety of insects to their vicinity. And having a wide variety helps promote balance, where no one insect species gets out of hand and goes on an eating rampage through your garden. Among the insect horde that these plants invite to your garden are species that like to munch on those bugs that potentially become garden pests. Also invited are pollinators - insects that go from flower to flower spreading pollen and enabling the plant to produce fruit. Yarrow, fennel, and dill are just a few examples. See my post on insectaries.
  3. Mulch maker - While nutrient suppliers build soil by pulling up nutrients that are farther underground, mulch makers build soil by providing a carpet of organic material on top of the soil. As Toby Hemenway explains in his book, Gaia's Garden, mulch is just composting in place. While all plants drop debris, the plants with soft leaves are preferred as mulch makers because their leaves compost the fastest, thus benefiting the soil more quickly. It is also beneficial if the plant can handle being slashed down multiple times in a growing season. Comfrey is one of my favorite mulch makers.
  4. Pest repellers - This group helps repel or prevent insect pests and/or fungal diseases. For example, radishes are good companions to squash and cucumbers by repelling a variety of beetles.
  5. Space sharers - Plants take up space both above ground and below ground. Space sharing is where different plants can grow very close together because their roots look for nutrients at different levels or where their stems and leaves have different growth habits. This is one reason that the Three Sisters pattern works so well: squash plants sprawl out over the ground, the corn stalks grow vertically above the squash, and the pole beans trellis up the corn. Great Garden Companions illustrates a below-ground example with a close interplanting of carrots, beets, and onions.

Companions

I have a few groups already put together. Please mention any additions or recommended changes in the comments section!
Group 1
•Peas, followed by Pole Beans
•Carrots
•Radishes, followed by Cucumbers
•Leaf Lettuce
•Spinach
•Caraway
•Fennel
•Lovage
•Marjoram
Group 2
•Peppers
•Onions
•Sunchokes (Jerusalem Artichoke)
•Lettuce
•Amaranth
•Carrots
•Coriander
Group 3
•Flint Corn
•Winter Squash (pumpkin, delicata, butternut, acorn)
•Pole Beans
•Nasturtiums
•Marigold
•Clover
Group 4
•Tomatoes
•Basil
•Onions
•Collards
•Carrots
•Parsley
•Horehound
•Cosmos
Group 5
•Eggplant
•Bush beans
•Dill
•Cosmos
•Marigold
Group 6
•Broccoli
•Kale
•Marigold
•Dill
•Beets
•Peppermint
•Zinnias
•Calendula
•Chamomile
Group 7
•Potatoes
•Flax
•Coriander
•Basil
•Marigold
•Sweet Potatoes

Summing Up

There are many ways and reasons to mix and match plants in your garden. Diversity is much more resilient, beautiful, sustainable and, in the long run, productive than block monocultures. Come up with a plant guild of your own and share it in the comments section. Also, remember to share any good references that you may have run across.

References