Nathan Strumfeld wrote:I'm just wondering- I have a large comfrey plant behind my shed. I want to split it and propagate the root into 4 or so new plants for under my cherry tree. It's starting to dip into the upper 30s/low 40s at night. Should I wait till Spring or is it ok to do this now?
I'd yank it, cut it up, replant it, and throw some chips down, that way it will be ready to pop in spring. My experience with Comfrey is it's darn near bullet-proof. If you don't want to take a chance just do it in the spring. I planted 5 root bits in spring and I have around 15 comfrey plants in my yard now. I'm planting comfrey next to every tree so I can just chop and drop.
Will the new plants have enough time to get established before the hard frosts of winter come? My fear is that those cuttings will freeze all the way through and the ongoing freezing and thawing over he next 5 months will kill those cuttings before they get a chance to root.
If it were me, I'd leave the plant in the ground for the winter, and then go ahead and spit it come spring time. Or, if you've got a sun room or south-facing porch where it doesn't get so cold, perhaps plant those root chunks in well-draining potting mix (like a 50/50 mix of cactus mix and potting soil) and let them overwinter in a warmer place. You aren't going to get much more than a couple of weeks of growing season before freezing weather renders them a dormant, so dividing them and planting them now just feels like there is no advantage whatsoever.
Just because it might possibly survive the winter doesn't seem like a good enough reason to do it now. Patience, grasshopper. It'll only take you 20 minutes to do the very same thing next spring.
If it's a large plant as you say, you can easily get 20 or 30 plants from it if you want that many. Every root cutting will grow a plant. If you want them to get big faster, do it as you say and use crown cuttings.