I was hoping someone here could help me. I live near some strawberry fields and they always cover their beds with black plastic in the winter. Why is this done? What are the advantages to this?
They probably grow strawberries as an annual crop, thus cover the rows to fumigate, sterilize, fertigate, and warm up the soil faster in the spring. Maybe mostly the latter. I suspect that the drip tubing is installed underneath the plastic by machine.
This, at least, was the annual routine in the vast acres of truck crops (tomatoes, strawberries) that I've seen.
Big Ag in action. Nurturing the soil community is not the first priority, as illogical as that may seem. Modern large-scale farming is an extraction process. Thus the arising of the term "sustainable agriculture".
According to a piece I read years ago all that plastic goes into landfills between each crop cycle.
Commercial strawberries are an incredibly intensively managed crop. If you have problems understanding that, this is not the conversation for you. rhizo got it basically right, simplied a lot, but close enough to count.
The plastic is used to "sterilize" the soil, in this case, that means the plastic cts as a greenhouse, causing weeds to germinate, but then die because of the heat under the plastic, the lack of sun because of the color. Of course, they could also use a lot of chemicals to do the job. Believe it or not, that would be cheaper.
And, yes, the plastic goes into the landfill. You know what plastic film gets to be like after some time in the sun? You can't exactly re-use the stuff. I suppose they could just plogh it into the soil...that sounds like a prime example of "sustainable agriculture". And the funny thing...there is a biodegradable plastic available, made out of corn. But it's made out of ge corn, so is unable to be utilized in certified organic production.
They cut slits in the plastic in late winter and plant. The plastic warms the soil giving them an early crop. They can get more money for the first crop of the season. The plastic also keeps the berries clean for harvest. Straw used to do the job and benefited the soil as well. Bottom line, money.
I've seen strawberry fields in California covered with clear film with a pink glue strip... is that different than the technique desribed above?
Should produce generally similar results. Apparently they aren't having weeds grow under the clear film, the black plastic would have the advantage of not acting like a greenhouse and letting light needed for foliage through.