Occulation - Ask Extension
Hello.
My wife and I are starting a small vegetable farm. My folk's property has prarie grass we need to kill off. Due to being out in Montana ...
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Occulation #947463
Asked October 21, 2026, 3:27 PM EDT
Hello.
My wife and I are starting a small vegetable farm. My folk's property has prarie grass we need to kill off. Due to being out in Montana this work season, I wasn't able to kill off the grass this summer. We want to do this without harmful chemicals. It looks like silage tarps are the best way to go, with the size of land we want to use (0.8 acres). My question is should we lay down tarps now or wait till the sping? I've read conflicting info about dormancy with grass in the fall. Some sources recommend tarping over the winter and others do not and say wait till spring. What do you recommend, with it already being late Oct here? Thanks for your help
Watonwan County Minnesota
Expert Response
Thank you for writing.
In general, I prefer solarization with clear tarps.
Occulation can be done. https://extension.umn.edu/garden-and-home/yard-and-garden/gardening-in-minnesota/solarization-and-occultation
The problem with doing it now is that cold is putting seeds into dormancy. One needs heat and water to get the seeds to germinate, grow and then die under the tarp.
So, its a bit late.
Your growing zone is 5a. I expected 5b. So in the spring, early April, water tarp (clear or dark your choice although I prefer clear because the light hits the soil and makes weeds fully germinate before dying. 5 weeks. Will take you to the last freeze date in May and then plant.
In general, I prefer solarization with clear tarps.
Occulation can be done. https://extension.umn.edu/garden-and-home/yard-and-garden/gardening-in-minnesota/solarization-and-occultation
The problem with doing it now is that cold is putting seeds into dormancy. One needs heat and water to get the seeds to germinate, grow and then die under the tarp.
So, its a bit late.
Your growing zone is 5a. I expected 5b. So in the spring, early April, water tarp (clear or dark your choice although I prefer clear because the light hits the soil and makes weeds fully germinate before dying. 5 weeks. Will take you to the last freeze date in May and then plant.
