[Carollan]

After a pretty disastrous spring,I decided  my autumn planted  3 year old rhubarb crowns should be given a helping hand ! I felt particularly fond of them,since I grew them from seed   I have watered them once a week really well and have been pleased to see them pick up from a near death.

Yesterday,the wasps from my wasp nest on the allotment,were attacking just one of the plants in force.The other plants were wilting a little in the heat,but not this one.They weren`t eating any aphids,since there aren`t any.I watched them.They were chewing the leaves but not going back to the nest.Do wasps really like rhubarb leaves??Or are they chewing the leaves and sucking the juice from them?

I tried putting a small bag of over ripe blackberries nearby,not many of them were interested.

Have any of you long time gardeners seen this before?

[Trillium]

I've never heard of this myself, but with nature, anything is possible.

At this time of year, wasps change their eating habits to prepare for winter, and they'll go after sweets and carbs.

Normally, rhubarb leaves are toxic due to oxalic acid, but its very possible that wasps aren't affected the same way humans would be, and are using the juices of the crisp leaves to fuel themselves (just what you needed, right?)

Wasps are usually attracted by spearmint, sweet fennel, queen anne's lace and yarrow. If you don't have any of these in your plot, then they'll go after the rhubarb. It might be worth planting one of these as a throwaway crop to deter the wasps from further damaging your rhubarb, unless you prefer to kill the wasps so they don't multiply for future seasons.

[Torgan]

I did notice the same thing happening to my rhubarb a few weeks ago, must have been about the same time as you.  There were a few wasps that seemed to be chewing away at top of the stalk where it meets the leaf rather than the leaf itself (although I didn't feel like disturbing them to check if there were more under the leaf!), the plant seems to be ok other than the die back that's happening just now.  There are some crystallised sugary drops on the stalk, I was guessing they were just after the sugar, they seem to have disappeared again though.  I don't have any other fruit so I guess that's the best thing they could find to eat.