Seeding the new forest garden

forestgarden dec2015A forest garden is a garden of perennial plants that produce food.  It is often designed to look “forest-like,” with trees forming a canopy above, and smaller plants creating a “forest floor” effect underneath.

As part of the Westchester Community Oven project, we had always intended to try adding a food forest garden to the Community Garden at Holy Nativity.

Since the spot chosen was under an asphalt parking lot for at least 30 years, the first step was some soil remediation.

Soil pH in Southern California

I’ve been thinking about soil pH lately – particularly since the oven project at the Garden will be creating an ongoing supply of wood ash.

pH is a measurement of the acidity or alkalinity of your soil. “Soil pH influences the solubility of nutrients. It also affects the activity of micro-organisms responsible for breaking down organic matter and most chemical transformations in the soil. Soil pH thus affects the availability of several plant nutrients.” (1)

Raised beds vs. Sunken beds

raised bed“To be a successful vegetable gardener you need raised beds,” the garden catalogs and East Coast garden magazines try to persuade us with effusive and glorious terms.

Consider what is behind their arguments: a drive for commercial sales, and a dramatically different growing climate.

East Coast gardeners raise their beds for two good reasons: 1) to be able to dig the soil sooner after a cold freeze, and 2) to keep the rootballs of their plants high so they won’t rot during extensive summertime rainfall. Neither of these is an issue here in Southern California. Thus their logical solution — raised beds — isn’t a good match for our Southern California growing conditions.

Root knot nematodes

someone else’s photo, that looks like what we saw

Yesterday in the Community Garden, we discovered that we are experiencing an attack of Root Knot Nematodes.  The beets we pulled up had failure to thrive, failed to form a beet root, and had tons of tumor-like growths on the hair roots.  Yuck.

The excess of one organism — to the point that we call them a “pest” — is a system imbalance.  It’s probably due to something lacking in the overall micro-ecosystem.

I’m sure our beets this year were weakened from lack of proper rain, and from excess high temperatures this season, so they were particularly succeptible.  My guess is that we probably have had low levels of root knot nematode everywhere for years, but thus far the soil ecosystem had kept them from flourishing and becoming an out-of-balance pest.

We grow organically, so that streamlines our treatment choices.  The goal is to regain the soil-ecosystem balance.

Building a Food Forest garden – cover crops

We’re designing a Food Forest garden, to be built later this spring.  We’ll be tearing out asphalt, cleansing and rejeuvenating the soil, and recrafting the space as a community gathering area with a cob bread oven and food forest.

Today I’ve been studying cover crops and compost crops for the “rejeuvenating the soil” part.