This is my useful and beautiful patch of comfrey, Symphytum x uplandicum ‘Bocking 14’ . It is a hybrid from parentage both rough (Symphytum asperum) and common (crossed with Symphytum officinale). The deep tap root of comfrey enables it to suck up nutrients from the soil which are then available to us gardeners through its prolifically produced leaves – the whole plant can be cut right down 4 -5 times in the growing season, the leaves being used for a host of different things that are listed below. I see a comfrey patch as an enhancer of garden health. I got these plants from the Organic Gardening Catalogue a few years ago now; Bocking 14 is a sterile clone, propagated through root cuttings, and doesn’t spread the way Symphytum is renowned for.
Comfrey Leaves Can Be Used:
1. As a compost activator
This adds nitrogen to the heap and helps it to heat up.
2. To mulch the soil
Layers of leaves makes a good thick mulch and provide food for worms and other soil fauna. The soil benefits from the action of the worms, which aerates it, and the addition of humus created when the leaves rot down into its surface
3. As part of a liquid feed (you have to be dedicated to horticulture to bother to do this)
You pack the leaves into a bucket and cover with water. It is advisable to cover this mixture with a lid because as it rots it will stink. After a few weeks you can dilute the resulting liquid (I would do it one part feed to ten parts water) and use it to feed your plants.
4. As a slug distractor
People who suffer from a surfeit of slugs and snails in their gardens, as I do, will try anything. As slugs are ‘cleaners’, scoffing any leaves that start to rot, the idea is to leave heaps of comfrey leaves in strategic places in the garden and allow them to wilt and go brown. This is supposed to attract the slugs away from your vegetable patch to another meal. However I am not sure if this is just providing a nice hiding place for slugs until they are ready to come and eat my lettuce. Probably you are supposed to frequently inspect the mini-heaps, and remove and dispose of the slugs at regular intervals.
5. As part of a fancy leaf mould mix
This makes a potting mix as it is too strong for seedlings. In a black plastic bag alternately layer 2 year old leafmould with chopped comfrey leaves. Layers should be about 3 or 4 inches thick. Check to see when the comfrey leaves have rotted into the mix and it should then be ready to use. This could take 6 months or less, depending on the time of year.
Although having the good intention to harvest comfrey leaves, I rarely do. The plants start flowering and looking majestic and get covered with bees – I don’t have the heart to cut them down! I think I have managed to do it around twice a season, and I’ve added it to the compost heap or used it as mulch. My challenge is to start making leaf mould this winter and look ahead to mixing my own comfrey potting compost.