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Covering gardens

comments (1) September 30th, 2009

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officersunflower officersunflower, member
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I have heard that covering gardens with black plastic in the fall will help suppress spring weeds fro sprouting/growing.  Is this true?


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Loosiana writes: I inherited a garden from people who obviously believed this was true.

15 years later, I am still breaking my back and my heart digging out their layers of black plastic sheeting, landscape cloth, lengths of carpeting, all manner of trash - which is RIDDLED with dense impenetrable mats of perennial weed roots which have woven themselves in and out of all this stuff. Their tough pointed roots pierce through black plastic and nylon loop pile and landscape cloth with gay abandon. Weed seeds fly in from surrounding farmland and sprout in carpet, and in the mulch and dust that lands on top of the plastic and landscape cloth.

This is a massive environmental problem which really needed heavy machinery to scalp the entire surface of the garden so that I could start fresh with organic mulches. It is impossible to pull weeds out of synthetic materials, and impossible to plant into soil that is covered with it. The earth underneath is pitifully depleted, compacted, sour and dead. It requires huge amounts of organic matter before it will grow anything.

The soil is a living organism that needs to breathe, to have oxygen and nitrogen and carbon dioxide moving freely through it, to have the sun shine onto it, to soak up the rainfall, to be broken up by frosts. Black plastic prevents all of these natural processes, and kills the soil life underneath, good and bad - except the perennial weeds of course! They run rampant underneath plastic, strong and undeterred on their quest for a chink of light, so dense that a garden fork can scarcely find a way through them.

If you have docks, couch grass, onion or rope twitch, buttercups, flatweeds, etc then black plastic is not the answer. I'm still trying to work out what is the complete answer, but a spray of Roundup over 200 square yards of heartbreakingly-weedy veggie garden a month ago, has reduced those monsters to desiccated shrivelled brown straw on top which is fairly easily hoed off.

I still have to mattock and fork out the huge volume of perennial roots which do not seem to have died off yet. Any opportunistic regrowth will have to be spot-painted with Roundup later. It is a case of grow my own food or starve right now - so Roundup was the only practical resort.

As for those nice juicy annual weeds - a light hoeing when they're small, or easy pulling when they are bigger, and continual application of layers of weed-free organic mulch (clean straw, pea hay, wilted mowings from your garden and your neighbours, untreated sawdust, etc) turns these weeds into food for the hungry worms who tirelessly feed the soil.
Posted: 7:24 pm on October 4th
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