Dahlia frost damage - Ask Extension
dahlias emerging after overwintering in ground got hit by last night's frost (why do they wait until 9:30 to tell you to cover vulnerable plants?), ne...
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Dahlia frost damage #633658
Asked May 10, 2020, 11:38 AM EDT
dahlias emerging after overwintering in ground got hit by last night's frost (why do they wait until 9:30 to tell you to cover vulnerable plants?), new leaves black. Will they recover or should I dig them up?
Thanks.
Baltimore County Maryland
Expert Response
Hi - That's unfortunate about your dahlias. The chance of recovery will depend on the extent of the frost damage. How many sets of leaves did your plant have already? Where all of the leaves damaged or just the top growth? If you still have some healthy green foliage and a healthy node (the point at which the leaves emerge from the stem), there is a possibility that you could get new shoots from the node. It will also depend on how recently you planted your dahlias out and whether they had a good root system developed already. If you do still have a healthy node on the stem(s), prune out the blackened foliage and see if you get new shoots. That's really all you can do.
Christa
Christa
These are tubers that overwintered in the ground, so should have good root system. How do I know if the node is healthy? About 2-3 inches of top growth black, will have to look more closely for any green. Thanks.
If the node area is still green and feels plump (turgid) not soggy, mushy, or discolored, it may still be healthy and able to push out new side shoots. You can pinch out the top 2-3 inches of damaged growth. Monitor to see if there is new shoot development (should happen in about 2 weeks or so if they are still good).
Christa
Christa
