to roof or not to roof!

[Pompeylottie]

on our allotment we have a 6' high raspberry cage about 5 metres long x 2 metres wide (roughly). We are moving all the raspberries out into another place on the plot as the cage is infested with bindweed and we want maximise the space available for other things.
After a good dig over to get as much of the bindweed out that we can, we thought of keeping the frame work and covering with plastic to create a sort of homemade polytunnel, we will probably grow tomatoes and salad bits there for the first year.

The question is - should we put a plastic roof on, or leave it open. The advantage of leaving the top off is the rain will do alot of the watering and bees etc can get in to do their bit. The advantage of putting a plastic roof on is it will be warmer. Any advice please?
Thanks.

[Aberdeenplotter]

on our allotment we have a 6' high raspberry cage about 5 metres long x 2 metres wide (roughly). We are moving all the raspberries out into another place on the plot as the cage is infested with bindweed and we want maximise the space available for other things.
After a good dig over to get as much of the bindweed out that we can, we thought of keeping the frame work and covering with plastic to create a sort of homemade polytunnel, we will probably grow tomatoes and salad bits there for the first year.

The question is - should we put a plastic roof on, or leave it open. The advantage of leaving the top off is the rain will do alot of the watering and bees etc can get in to do their bit. The advantage of putting a plastic roof on is it will be warmer. Any advice please?
Thanks.

A polythene covered structure of any sort hugely increases the number of crops you can grow and extends the season of growth for others. However, in a situation where weed growth is an existing problem I would seriously consider planting that area in potatoes in the coming season so that the ground can be cleaned up. During the Potato growing season, the ground is moved first of all when dug, then when the crop is planted and again when the haulms(shaws to us in Scotland)are furrowed up. From then on, the ground beneath the haulms is deprived of light and very few weeds will germinate and then the ground is moved again when the crop is lifted.

You should end up with clean ground very suitable to cover with a tunnel even if it is a makeshift one.