Occultation CoversIn The Garden

Dateline: 17 May 2014

One of my garden beds with an occultation cover. Click the picture to see an enlarged view.

As I explained back in Deliberate Agrarian Snippet #13, I have decided (after a lifetime of resisting the idea) to utilize plastic as a mulch in my garden. I was persuaded to give plastic a try because I do not have the time to run my Planet Whizbang mail-order business and keep my whole garden properly cultivated. Besides that, Jean-Martin Fortier's book, The Market Gardener convinced me that black plastic makes good sense.

Fortier uses the plastic in two ways. First, he uses it to cover his 30" wide beds that are prepared-for-planting….

[W]eeds germinate in the warm, moist conditions created by the tarp but are then killed by the absence of light. This weeding technique, described as "occulation," is widely used by organic growers in Europe.

I've never heard of the word, "occultation" and a Google search of the word "occultation" and "garden" didn't turn up anything. Although the concept is nothing new to most gardeners, I think the word is. Here is what else Jean-Martin Fortier writes…

We have been using 6mm black plastic silage tarps in the garden for almost a decade now, and I can say without hesitation that their usefulness is one of the reasons behind the overall success of our operation. This passive and efficient practice takes care of part of the weeding chores while we are getting work done elsewhere in the garden.

I don't have a 1.5 acre market garden, and don't have a black silage tarp, but I decided to use some 48" wide lengths of This High-Quality Landscape Fabric for occultation covers in my garden, as the picture at the top of the page shows. 

The tire sidewalls, which I have been collecting and using in various ways in my garden for years, do a fine job of holding the plastic in place. After being covered a few weeks, the soil under the covers is weed-free and moist. The tilth of the soil under the covers is dreamy-nice.

After using the plastic for occultation covers, I folded it in half and laid it between the beds, as shown in this next picture…

When a bed is harvested and not growing anything, I will re-cover it with an occultation cover to keep the weeds from developing. That is what Jean-Martin does.

Thus far, I'm liking this landscape fabric. I did, however, find out that it will unravel on the ends if not heat-sealed, as this next picture shows…

Occultation covers made with landscape fabric will fray on the ends if cut with a knife. I had to re-cut the ends with a hot knife to get a sealed edge. You can also seal the ends with the heat from a propane torch. 

I'm impressed with the durability of the landscape fabric. It remains to be seen if it will last 10 years, as the manufacturer says it will. But the following YouTube clip is evidence of just how strong and long-lasting the product is…