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Rhubarb problem
ommthree
Posts: 314
Hello all,
My rhubarb, which has been fantastic since I planted it three or four years ago, has developed a problem with its leaves.
The whole plant seems like it's dying back. Does anybody know what is causing it?
There is an aphid problem, and associated ants, but I doubt if that could be the problem. There are loads of ladybird larvae helping out with that. I did see a fast-moving black and white beetle at some point.
Thanks,
Owen
0
Posts
If you have ants, the soil is too dry for rhubarb and they may also be nesting in among its roots which means they're hanging in air instead of in contact with the soil and taking up moisture. Give the whole plant and its roots a very thorough soaking - gallons, not litres. Then loosely fork over the around the base of the plants to help fill up any holes they've left and water it again before mulching with plenty of organic matter to provide nutrients and keep in moisture.
Thanks Obelixx,
It's actually pretty moist down there, and we've had a huge amount of rain in the past week or two. I do mulch a couple of times a year with compost. And I've never had a problem like this before with the brown blotches on the leaves.
Could it be anything else?
I have recently left a garden in Belgium where we had high average rainfall and fertile soil and lots of rhubarb. However, one summer we had this problem with ants moving in and nesting under their roots and it weakened the plants. Do try giving yours a serious soaking because it's easy to underestimate how dry their roots can be.
Ants move aphids onto plants and then protect them from predators because they use the honeydew they excrete to feed the young ants when they hatch. That is probably what's causing the spotting on your leaves.
You can also encourage ants to move on by watering copiously with a solution of 5 litres of water to one small bottle of essential oil of cloves from a health shop or pharmacy. They hate the smell and move away. repeat as necessary.
Thanks Obelixx.
Switzerland here. It's rained a bucketload in the last week, so perhaps that will fix the problem. I'll follow up with some serious watering when things start to dry up, and see if it helps.