Musings on Polyculture — Part 1

Yesterday I stumbled on the concept of mixed vegetable gardens courtesy of Anni’s Perennial Veggies. First let me provide a little background. In the natural ecology of the forest we can see a structure.

Woodland Structure: Offwell Woodland & Wildlife Trust

Ecologists name seven layers: the vines, grasses, ground level plants, the herbaceous layer, scrub, small, low trees (sub- canopy) and large trees. (canopy) This system which encompasses a variety of plants is a polyculture as opposed to a monoculture where only one species is dominant.

The forest garden tries to emulate this concept by establishing a variety of food producing plants which replicate this pattern of the diversity and layering of plants in the forest.  The mixed vegetable garden replicates this pattern of plant diversity and  levels using traditional annual vegetable

Anni's Polyculture courtesy Anni's Perennial Veggies

plants.

The Permaculture Association UK  has developed instructions on this method of planting which they say was originally developed in Nepal and have adapted to UK conditions.  Toby Hemenway’s book, Gaia’s Garden lists a few polycultures.  This Mixed Vegetable Garden pamphlet  identifies  plants by  plant families and layer and encourages you to develop your own polycultures.

UK Permaculture is currently running tests to assess the benefit of this approach in the UK.  Planting 12 crops: onions, kale, beans, peas, corn, spinach, beets, radishes, lettuce coriander, rocket (mustard greens) and marigolds, they suggest you:

  • sow your onions in the ground and start your beans and kale indoors in march (UK planting times)
  • plant your peas outdoors and start your corn indoors in April
  • plant out all of your transplants and sow all the other seeds in May.

You sow basically once and then pick everything as it comes in. I’ve been thinking about my fall garden and so I kept searching for the fall planting times for the cool weather crops using this mixed gardening method. There is no fall planting! You plant  the lettuce and greens in March and harvest through the summer until October without a second planting (!!!) Like in a forest, the shade from the canopy and understory protects the ground cover.

That’s almost unbelievable to me here in Georgia . I’m guessing that the UK is part of the temperate deciduous forest biome just like we are here in the southeastern US.  I’m in hardiness zone 7, most of the he UK is in hardiness zone 8 (another surprise .  I would have guessed it was much cooler.  A little research shows that the metro-Atlanta region has more rain than the UK and is a little cooler.  Central GA  does have much more sunshine, almost double the annual hours of sunshine in the UK.]

In summary, with the mixed vegetable garden:

  • the work to sow the garden is less than with a traditional garden
  • the polyculture is more resistant to pests and diseases
  • the polyculture has fewer weeds
  • the yield is greater than that of the traditional garden

This is something I really want to try next year.

Also see Musings on Polycultures pt 2.