Interesting question, Max. One concern, I didn't know about.

My rhubarb takes quite a bit of abuse. A late harvest is part of that. They are doing fine. What I make sure of is leaving them alone through the summer. That's for the plants' benefit.

Here is what Iowa State University says about harvesting:

"Is it safe to use rhubarb after the plants have been exposed to freezing temperatures? The leaves of rhubarb do contain oxalic acid and soluble oxalates. Consumption of rhubarb leaves can cause nausea, vomiting, abdominal pains, and even death. The concern expressed by some individuals is that the oxalic acid and soluble oxalates would move from the leaves to the stalks upon exposure to freezing temperatures. In fact, however, the movement of these compounds into the stalks is not a problem. Gardeners should examine their rhubarb and base their harvest decision on plant appearance. Cold damaged rhubarb leaves will shrivel and turn black. Damaged stalks become soft and mushy. Damaged rhubarb stalks should be pulled and discarded. Any new growth which emerges later this spring would be safe to eat. Rhubarb plants showing no sign of damage are fine and can be harvested."

I hope that information helps.

Steve

That is very interesting info Steve, thanks! Maybe yet another myth busted? My stalks are not mushy, and the only damage to the leaves is from grasshoppers (gggrrrrr). I hope they got indigestion at least.