Last edited Wed Mar 30, 2016, 11:05 PM - Edit history (2)
They work really well if you live somewhere cool and need to keep them warm early in the season. I start my tomatoes indoors in late February, and just moved them outside into the wall of water containers. I'll leave them in there until mid May, which is when temps are consistently above 40 degrees at night around here, and they'll be busting out of them by then. I have ripe tomatoes by July 4th, weeks before pretty much everyone else in my area.
They are a bit difficult to manage, and cells leak, compromising the structure, but you can get repair sleeves. For me, the effort involved in filling them and moving them around is worth it.
They work better than a traditional greenhouse for keeping plants warm at night because the water absorbs heat during the day and releases it slowly at night. Basically, tomatoes need to be above 40 degrees at night to avoid shock. So if your nights are still getting close to that, these will help, but they are difficult to handle. It's a trade off that you choose, for earlier tomatoes - but you have to start your tomatoes earlier too - starting them at the same time and putting them in these won't help much, if at all.
I don't buy the red ones. I like the transparent green ones. The opaque green ones don't let as much light through.
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