By Elliott
Permies has been given permission to utilize a small garden plot in the "Food for Thought" garden near the agriculture building tucked into a far off corner of campus. This garden consists of many terraced plots built into a hillside and it is used by the organic gardening class (highly recommend if you want to learn more about small scale veggie gardening). When the horticulture professor asked me what plot I wanted, I picked the largest, yet most infertile site. When I picked it last semester, there was literally nothing growing in the rocky rubble that could barely be called soil. The site had been recently excavated so it was in a very early stage of succession. Behind the plot is a very steep ledge of loose sediment that appears very erosion prone. However, there is chain link fence material that was put up to keep it in place. While many people may see that as problematic, I saw it as an opportunity. Because it was essentially a blank slate that gives Permies the opportunity to design the garden any way we want. There's no having to debate about cutting existing trees and vegetation that might get in the way of a garden.
About a week ago I visited the garden again (after we dug the rocks out last semester) to see if it had progressed. Yes! Weeds such as edible Sow Thistle and Dandelion were now growing, adding much needed nutrients and organic matter to the degraded soil. I measured the dimensions of the garden, and sketched out the shape onto paper.
Permies has been given permission to utilize a small garden plot in the "Food for Thought" garden near the agriculture building tucked into a far off corner of campus. This garden consists of many terraced plots built into a hillside and it is used by the organic gardening class (highly recommend if you want to learn more about small scale veggie gardening). When the horticulture professor asked me what plot I wanted, I picked the largest, yet most infertile site. When I picked it last semester, there was literally nothing growing in the rocky rubble that could barely be called soil. The site had been recently excavated so it was in a very early stage of succession. Behind the plot is a very steep ledge of loose sediment that appears very erosion prone. However, there is chain link fence material that was put up to keep it in place. While many people may see that as problematic, I saw it as an opportunity. Because it was essentially a blank slate that gives Permies the opportunity to design the garden any way we want. There's no having to debate about cutting existing trees and vegetation that might get in the way of a garden.
About a week ago I visited the garden again (after we dug the rocks out last semester) to see if it had progressed. Yes! Weeds such as edible Sow Thistle and Dandelion were now growing, adding much needed nutrients and organic matter to the degraded soil. I measured the dimensions of the garden, and sketched out the shape onto paper.
So on to the design..... (bear in mind that this design is tentative and I want to work with Permies as a group decide what we want). One of the most important aspects of design is to list your goals. For me, the number one goal for this garden is to build rich soil which the site lacks completely. Gaia's Garden by Toby Hemenway, recommends several techniques to build soil that I incorporated into the design: sheet mulching, hugelkulture, and cover cropping. Sheet-mulching consists of a cardboard barrier and multiple layers (often a foot or more) of organic matter on top. I'm thinking some invasive Primrose Jasmine leaves would be a good source of organic matter to add. Lawn clippings, hay, manure, leaves, compost and rotting produce are also good additions on top of the cardboard. This is essentially composting in place.
A very similar similar technique of composting in place is hugelkulture. Instead of the main layer consisting of a mulch of leaves or straw, the bulk of the organic matter consists of logs and branches. I'm thinking that the abundant invasive ligustrum would be a good source for this. I can't seem to find any sources that says how this tree decomposes (some trees are not good for hugelkulture due to slow decomposition or chemicals that harm other plants). Either way there are too many of those trees chocking out the native vegetation and it is a great way to increase yields. I plan on laying the logs down covering with other layers of organic matter with a final coating of soil. On contour this will provide a long skinny mound that will act as a berm, preventing excess water and nutrients from washing down the slope.
Another technique used to build soil is cover cropping. This technique uses hardy plants that add fertility back to degraded soils. They do this by adding bulk organic matter to the soil, accumulating nutrients, and fixing nitrogen. Nitrogen does not enter early on in succession. After visiting the Lady Bird Johnson Wilflower Center last week I encountered a gorgeous native annual nitrogen fixer with lovely yellow flowers, Partridge Pea Chamaecrista fasciculata. Evidently it makes a great cover crop.
Fava Beans, Clover, Vetch, and Austrian Winter Peas are also great nitrogen fixing cover crops. The Fragrant Mimosa is a hardy native nitrogen fixing perennial shrub I am also considering adding. This will add some dappled shade and nitrogen for some future veggies underneath.
To build soil and accumulate nutrients, other plants I would like to add this semester are rye grass, sunflower, plantain (the weed), rapeseed, buckwheat, chicory, lambs-quarters, and daikon radish. And because the soil is so degraded I think it would be a good idea to add a relatively thin top dressing of compost before planting the cover crops.