As most of us know, usually from personal experience, gophers and invading tree roots are a frequent problem in our gardens. My neighbor Paula Barsamian had built several raised beds in which to grow vegetables over the years in her small garden but eventually, in each one, a gopher got through the wire as it disintegrated in the bottom of the bed. And in each one, tree roots grew up into the soil and began stealing all the nutrients and water. Frustration drove her to do some research. Online, she found plans for a raised bed design that used galvanized corrugated sheet metal as the sides but she modified it to overcome her specific problems.

(I had intended to include the link to that article but found that the domain was allowed to lapse so the link is no longer valid. However, there is a photo from that original article here: https://www.pinterest.com/pin/433119689134727124/.)

Barsamian’s basic 4 foot square box is made from corrugated sheet metal roofing attached to corner pressure-treated 4×4 posts and framed with PT 2x4s; the metal overlaps at the inside corners so the soil doesn’t come into contact with the PT, ensuring that there is no danger of soil contamination by the toxic metals in the wood. The top of each box is 31 inches from the ground, making it the same height as the average dining room table – a good height for easy reach. In the bottom of each bed, ½” hardware cloth is attached to support more corrugated metal that acts as the bottom of the “container.” (Both the hardware cloth and the sheet metal prevent gophers from gaining access. The metal is overlapped to hold the soil and the corrugations direct excess water to the sides where it drains away freely.

So that took care of gopher access but how to prevent tree root intrusion? Barsamian’s solution was to rest each box on concrete blocks at the corners and along the middle (to support the weight of the soil and plants) so that there is no ground contact and therefore no way for tree roots to grow up into the boxes. A year later and her boxes remain gopher and tree root free. The boxes were filled with a mixture of rotted horse manure and potting soil, a drip system was installed and vegetables planted.

This summer, Barsamian’s boxes are prolifically producing tomatoes, squash, beets, peppers, eggplant, green beans, chard and some herbs. When she noticed some damage to her leafy greens from critters like squirrels, she created a cover made from hardware cloth bent to exactly fit one box but standing above the soil level about 16 inches. The cover permits the plants to grow freely while still allowing sunlight and air movement to reach them, but prevents any critters from taking her harvest. The cover is easily lifted when she needs to tend the plants to or harvest.

Since my garden also was plagued by gophers and invasive tree roots, I was of course inspired by the success that Barsamian was having with her boxes. Another helpful neighbor who happens to be a building contractor helped me build (well, actually I have to admit, he did the actual building while I “supervised”) first a long narrow box that fits under my front south-facing windows, and then a second square box with the same sun exposure but on the side of my house. Several years earlier, I had taken down a 3 foot high cedar fence.

Since the lumber was in perfect condition, I had saved it for some unknown future use. (I admit to being something of a packrat with potential garden materials.) Now inspiration struck: because my boxes were in my front yard where I’d prefer they present a somewhat more “formal” appearance than the sheet metal sides would provide, the metal could be covered with the salvaged fence boards, making it appear that my boxes were entirely wood. My contractor neighbor took that inspiration one step further, adding decorative caps atop the corner posts and dark brown gutter material that was fabricated by a local gutter installer to cover the top edges of each box, not only dressing up the appearance but protecting the end grain of the redwood fence material from weather and potential rot.

I filled the boxes with good soil, rotted manure and compost, added a drip system and planted vegetables and flowers. My plants are thriving and the attractive and well-built boxes are an asset to the overall design of my front garden, causing passersby to stop and say how much they like them. Thanks go entirely to two good friends who happen to be neighbors!

Garden tips are provided courtesy of horticulturist Sharon Hull of the San Lorenzo Garden Center. Contact her at 831-423-0223.

Source Article