Why are you using the row cover? Bt works for me for caterpillars and is inexpensive. Seems like a better idea in the peak of summer too when the cover will make the plants even hotter IMO.

I use it because for some reason, my garden is lousy with brassica-eating insects. Kale, broccoli, etc. get chewed up overnight. It's a desperate measure that's working so far.

Exactly how tall are they? What are you using for row cover and how do you have them tented? Each plant stalk will normally support its own insect barrier tent as it grows or a row of plants supports its own tent. Either way row covers are used for season-long protection so you wouldn't remove them.

Dave

Thanks! Mine aren't as big as those in the photo. I only want to remove the row to watch the plants grow. Not a good reason to remove it, admittedly.

IMO row covers are the best invention for gardeners since pockets on a shirt. For years I used BT, and it NEVER gave the protection that row covers give. And so much easier!

This is the cabbage I just harvested in the peak of summer with only Bt treatment.

Of course YMMV and we all have different experiences. Bt only protects against caterpillars, it doesn't help against other pests.