Cutting back perennials!

[Paul Paulsen]

Should most perennials be pruned to ground level after a hard frost or is it best to wait until early spring?

Or is there no hard and fast rule and depends on the plant?

Thanks PWP Zone 4

[Jim Kingdon]

If by "perennial" you mean a plant which is going to die back to ground level anyway, it doesn't much matter. It might not die right at the hard frost (it might be sooner or later, depending on the plant). But once it does, you can leave around the seed pods for birds or if you like the look, or prune it. Either way is fine. This is assuming the plant will be coming back from new shoots anyway.

Evergreens or woody shrubs/vines are a different matter. That one depends on the plant a bit more, but many of them would not take well to being pruned so drastically.

Then there are plants, like black eyed susan or evening primrose, where the old flower stalk dies, but they have small green leaves all winter. In those cases you can prune the flower stalk whenever it dies but you leave the leaves.

I guess I keep thinking of special cases so I guess it kind of is "it depends on the plant".

[Kay Lancaster]

The standard rule is "clean up ASAP". When research has been done, it's been found to be beneficial to leave the old leaves and stems as long as possible.

Kay

[FarmI]

Wait until spring. The dead stuff protects the plant.

[Jim Shaffer]

But it also hosts mold and rodents, so if you find you have a problem after one year, clean up that area the next year.