Friday, July 03, 2009

Patch Design

You ask, we answer! Lindy wanted to know what we meant by "initial patch design." The short answer is that our design process follows the permaculture principle of "design from patterns to details," which means that while we've done lots of large scale work on the property plan, such as choosing where to put buildings and gardens, we haven't done much small scale, plant-specific design. Now that we're actually beginning to plant trees, that has to change. The process we're using is called "patch design." Read on if you want the nuts and bolts.

A "patch" is essentially a garden plot, though it may not always look like a standard raised bed or have paths running along side it. Every plant in a patch, if it's well designed, will follow one or two important rules. These rules apply no matter the shape size or style of the patch.

Rule #1 is pretty much a golden rule - no two (or more) species should be forced to compete with each other. The permaculture name for this is a "resource partitioning guild," and it means that to design a patch we need to look at root structures, sunlight, nutrient needs, water needs and the ways that the plants reproduce. Some of this is obvious to any gardener - you wouldn't likely put your tomatoes in the shade or mixed in with raspberries. The tomato plants might survive, but they would hardly flourish.

There are some exceptions - the classic forestry exception is to closely space trees so that the competition drives them directly and rapidly up, toward the available light, making for straight, high quality timber logs. Another is to put pressure on a expansive plant to control it's ability to spread.

At the same time, though, many gardeners, in an effort to keep competition to a minimum, space plants far apart in bare soil, which just creates opportunities for nature to fill those niches - mostly with weeds, right? So we're always fighting nature's opportunists, who are just trying to do their job. With a permaculture patch, we're doing our best to design with a wide variety of plants (a polyculture) so that all of those niches are filled with plants WE want. So we minimize competition within the patch but fill all the spaces that nature could exploit. No more weeding!

Rule #2 is optional, but a big bonus - plants within a patch should support each other and the larger environment. This is often known as a "mutual support guild" and is what really starts to make a permaculture plot shine. Many folks will recognize the three sisters planting (corn, beans, squash) as a mutual support guild which has the added advantage of providing food for us. Imagine different sets of "three sisters" (or five sisters, or twenty sisters) plantings to benefit butterflies, or hummingbirds, or soil quality. That's what we're working on.

In this specific case, we're building a patch that has two interlocking support guilds inside of it. We have a red pine plantation which we will slowly remove, leaving acidic soil in it's place. Our patch design is focused on building soil, using lots of big leafy nitrogen fixers and dynamic accumulators (who bring up phosphorous, calcium, magnesium, etc. from deep in the soil and release it as they shed their leaves or other herbaceous mass). It's also focused on supporting our new beehives buy providing lots of pollen and nectar sources. All of these plants, shrubs and trees need to flourish in acid soil and in the partial shade created by the pines that aren't removed yet. They also need to minimize competition and support each other, as well as build healthy soil (which should slowly begin to rebalance towards neutral pH) and support lots of bees, spiders and birds.

We spend a lot of time looking at plant databases and catalogs. Each plant is a puzzle piece which may or may not fit into the big picture! Dave Jacke's Edible Forest Gardens Vol II has been a constant companion.

Hope that helps! We'll have more details about our specific plant choices soon!

1 comment:

turtlewoman said...

Hi, Brad. Thank you for such a complete and well written answer. Although I hold a PDC I had not - or perhaps simply do not remember -the specific term "initial patch design". Now that I understand what it is I am going to add your answer to my permie notebook. :-D

Many thanks - Lindy