I live in SC, zone 7B. I have had comfrey growing now for 2 years. This year, I see no shoots coming up. I am not sure if this is normal, as I would have thought with all of the rain and warm sunshine, something would be peeking out of the winter mulch cover.
Comfrey grows like a weed in the PNW. Mine gets huge to the point I have to start with the 'ring of death' in early spring - I toss a cut-off plant rim over the emerging plant and dig out anything that is beyond its allotted 16" spread. It grows very quickly and the bees absolutely mob the flowers. Then it all suddenly flops to the ground at which point I cut it back to about 3" and the cycle starts anew. I think I got about 3-4 flushes of growth/flowering last season. It also makes a very nutritious compost, particularly for tomatoes.
I would also be surprised if your comfrey has died Moxies_garden. I suspect with patience you will soon see the new growth.
The comfrey leaves can be used to make a compost tea to water plants. The leaves are rich in potassium.
Or the leaves can be dried a bit first and turn into the soil to benefit it. The roots of comfrey tend to draw nutrients to the plant and to the surface soil.
For medicinal use, it is recommended for external use only, either as a salve or a compress. When used internally it has been known to cause liver damage.
I haven't found mine to be too agressive here. Mine also doesn't reproduce by seed, only root division or runners. I believe it is Bocking.
I checked them again today. Nice warm and sunny day, 79*. I have 3 plants, and none of them are sprouting anything. They had leaves up until January, then they died. The leaves. The roots should still be okay though.
I am growing comfrey to try to learn the medicinal uses of the plant. This is the first time I have been able to grow any herbs at all.
My comfrey also seems kind of wimpy- considering its reputation for world domination. There some little leaves showing.
I weeded in the garden and threw all the flowering weeds( deadnettle and bittercress) around the comfrey. I figured the comfrey leaves will cover and choke anything that sprouts from those weeds, the comfrey leaves I can harvest for nitrogen and potassium without seeds.
sallyg- I looked today when I was outside. Nothing. Not a peep, or little green leaf anywhere. :( They've done great for the 2 years I have had them! They were growing up until December. Then, they died back. Do they need to go dormant for any length of time?
I am glad it came up finally. Now I am waiting on the rhubarb. I am trying to grow an herb garden, but some things are iffy in this zone. And, I have never had the chance till recently to try to grow one.
Funny how our microclimates vary. I'm on the west coast but in about the same zone as Moxie. My comfrey is getting ready to flower for the first round. I get blooms followed by a total collapse of the plant at which time I cut it back to 6" and it regrows to bloom again, usually 2-3 rotations per season. Here's full bloom from last year mid-May.