Hello, I just subscribed to Dave's Garden & tried to ask this question in the Rocky Mountain Gardening forum. It appears that this forum has had no activity for a long time. Too bad. Anyway, I would like to know if it is OK to cut back agastache now in the Grand Junction, CO area. We've had a warm winter & things are blooming much earlier. However, I was told years ago not to cut back agastache until April.
Also, I would like to know if it is OK to cut back lavender (established plants) now & how far back to trim them. Thank you!
Cutting Back Perennials
valygirlgj
Mar 25, 2015
I just heard a podcast last weekend that indicated that Agastache can be a little tricky about being cut back but I don't have the details since I don't grow it. Lavender is also fussy and I've heard that you can't cut it back into brown wood. If no one here can give you more specific info, do some more research online before trimming those plants.
I wait until mid-April to cut back Agastache since for me, it has proven to sensitive to spring freezes. I live in the Chicago area and sudden freezes into April are quite common.
Remember that lavender is not really a perennial but a sub-shrub. So doing more than a light trimming this time of year could result in a dead or permanently damaged plant.
I haven't cut back Agastache. Mine looked beautiful and full last year.
Edited to add:
I just read today one is suppose to cut back the Agatache after you see new growth from the soil. I suppose that must have been what I did last year. :( I have yet to cut mine back this year; still no green growth.
This message was edited Apr 1, 2015 6:46 PM