What nickmccann said! Try to get professional frost insulating material. A good way to do it cheaply is what I did, and buy it from a nursery
used. Way cheaper. For my 12 mats I got a roll of used material 15ft by 40 ft and cut it to fit. Full price was $4.00 a ft --- 160.00
See my gallery for other pics. Wrap around pstem like a hot dog bun. Fold over the top and the one side and use black binder clips - cheap in bulk boxes from Office Despot.
First cut off 1/2 of the oldest leaves and fold up the rest and tie with velcro tape from Home Despot.
If the pstem is very tall snap the leaf and fold down. These leaves will get cold burnt but they protect the pstem.
One more thing -- for the temps you get double wrap the pstems and make sure to to cover up all the way down to soil level. Invest in a banana trim knife - you're gonna need it when the
leaves turn brown. And I don't mean
in the fall.
Dan