Does covering grass with plastic tarps kill beneficial organisms?

[celiacjean]

Does covering grass with plastic tarps kill beneficial organisms? I have been reading that the beneficial organisms are also killed along with any unwanted weeds, weed seeds, harmful bacteria etc. I don’t have enough cardboard to cover my grass completely but do have tarps that I would like to use but do not want to kill of the beneficial organisms that I need in my soil.

[Cleansweep]

Not thought to be correct.
In UK climate, the sun is unlikely to raise the temperature under even a black polysheet to the required temperature to sterilise a soil profile, many organisms are mobile and can retreat.Similarly, a buried seed cannot (unfortunately!)be killed. If youve ever visited a forest fire site after the first subsequent rain, you would realise nature will return.
I would not personally lay any plastic as a long term remedy, but it can be a useful control tool.

[celiacjean]

Thanks Cleansweep, I am in Nova Scotia, would use the plastic tarps to kill the grass and then remove once that is accomplished.

[celiacjean]

Thanks Cleansweep, I am in Nova Scotia, would use the plastic tarps to kill the grass and then remove once that is accomplished.

[earthnut]

Even if the plastic does heat up enough to kill microbes, after the plastic is removed the microbes quickly re-colonize from the surrounding soil. So long term, it’s not a problem.

[celiacjean]

Thanks Earthnut, never thought of that, guess they would move to an uninhabited spot once the plastic is removed. Good point.,

[RayS]

I agree with earthnut.
I’ve used weed control fabric, plastic sheeting and tarps over the years to kill off grass in areas I want to grow vegies in. Never had any issues, even in areas where I’ve left it place for a full year. Under plastic and tarps the soil does dry out over time, at least where I live. When I uncover it, I either water it thoroughly then cover with mulch and plant it out or I mulch it and wait for good rain before planting.
A way to be confident that life is returning is to add a bit of good homemade compost around each plant or on top of each seed.

[celiacjean]

Thanks Ray, getting more confident now to use plastic tarps on my grass to kill it off, how long does it take to do the job so it is good and ready to plant veggies in?

[RayS]

I’ve left it for as little as two months in late spring/early summer and had pretty good results. Exceptions are the running grasses like couch. To deal with those, I dig an edge around the area covered, at the time of covering, to sever the stolons/rhizomes of the runners so they can’t continue to feed the part of the plant under the tarp. Perennials like dandelions aren’t killed off of course but they can be dealt with one at a time once you’re growing stuff. Just don’t let any of them set seed.

[celiacjean]

Thanks Again Ray, I have just put down (Apr) all the plastic tarps that I have on top of the grass which contains lots of weeds and they are held in place with large rocks and pieces of wood to keep them in place for when the wind blows. I will update as soon as there is any progress with the test. Jean

[celiacjean]

Thanks Again Ray, I have just put down (Apr) all the plastic tarps that I have on top of the grass which contains lots of weeds and they are held in place with large rocks and pieces of wood to keep them in place for when the wind blows. I will update as soon as there is any progress with the test. Jean

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