12 May 2015
Comfrey is permaculture’s darling for the herb layer- it’s a dynamic accumulator pulling minerals from deep in the soil, the leaves make a mineral-rich mulch or compost tea, the leaves and the roots are strong medicinal herbs, and bees of all kinds love the flowers. When it comes to stacking functions, comfrey is tops.
Comfrey was one of the first plants I wanted to introduce to my fledgling forest garden back in 2012 so I ordered some seeds soon after we moved in. I started those seeds in pots in the greenhouse. When they got big enough, I planted them out in the garden. The original idea was to have the plants bracketing each of the larger beds with fruit trees. That summer all but two plants died. The two that remained stayed about the same size for the rest of the year, a half-hearted spray of flowers and then a few leaves flattened against the ground. The first frost came and they both froze back almost to the ground, so I mulched them thickly with straw and waited to see what would happen.
That next spring, the plants exploded. They both flowered heavily and started producing the true comfrey leaves. Late in the fall I cut a bunch back for the first time and used them for mulch around the other plants. I hadn’t dared cut them back in the summer. What helped these particular plants survive? What changed? What helped them thrive? I really think it was a combination of factors:
- The fruit trees grew taller and gave both plants some much-needed late afternoon shade.
- The log borders they were both planted next to rotted significantly, making some rich humus that held water better.
- Their roots got large & strong enough to withstand the late summer heat.
This past winter was very mild. Neither of the comfreys died back completely and they both exploded in early spring. Then a few seedlings popped up around them, especially around the one that gets the most afternoon shade. I transplanted one of the seedlings to the base of a struggling peach tree.
Notice that the seedlings are also tucked in next to the log border, where the roots of the comfrey are protected from the heat and the soil is especially rich. I do not irrigate anything past the establishment phase and they have received no extra nutrients beyond thick mulch and some spring compost over the entire bed.
Yes, you can successfully grow comfrey in my area of Florida without constant irrigation. Give them some shade. Plant them close to rotting wood so their roots have a cool moist haven. Most importantly, be patient- it may take them a year or so to really get established. I’m excited that next year I’ll have enough seedlings to trade or sell!
This all being said- I am not sure that comfrey is the best plant for our climate and needs. It does shade the soil. It does get big and come back strong so it can be chopped and used as mulch. It is a strong medicinal. The bees do love it. However, there are other plants which are easier to grow which might be a better choice than comfrey if you’re only looking for chop & drop and feeding bees. Tithonia diversifolia grows crazy fast, thrives in full sun, does not need irrigation past establishment, bring bees and other pollinators in droves, and can be cut multiple times per season for biomass. Another possibility for subtropical climates is ironweed, Vernonia gigantea, which has all the same benefits as tithonia and more readily self-seeds. If you’re just looking for a plant that produces lots of biomass quickly for c&d, then choosing something easier than comfrey is probably a better use of your space.