Not all pretty flowering plants in small, four-inch pots siting on the nursery bench are as innocent as they appear. Beware the sneaky aggressor! About five years ago the delicate and rare clear blue color of the comfrey blossom, shyly wooed me into taking it home. What could one more plant hurt in the side garden abutting the wild side of the neighbor’s yard hurt? Well, it hurt plenty. I have been cursing the day I planted it.
Comfrey spreads incredibly fast. It is a hardy perennial with a deep and extensive root system. And its seed drop and are spread to create new plants elsewhere. The neighbor loves it and encourages its spread which doesn’t help my eradication efforts on my side of the property line. I suppose it makes a better fence than wood and nails, and he enjoys the view. The bees enjoy the flowers, too. Dozens of honey bees can be found busily entering flower after flower, not caring how close I get to almost petting them.
Comfrey is botanically known as Symphytum sp. and is a member of the borage family. The Latin name means ‘grow together’. It was first brought to America with the English as a healing herb. I contains a high level of the chemical allantoin which aids in cell formation, healing. It also is reported to contain pyrrolizidine alkaloids, known to cause liver damage when taken internally in large amounts. The leaves can be crushed or bruised to be placed on external skin areas to heal wounds and broken bones. I only use the plant as an ornamental and to spread into the neighbors neglected ‘wild’ area.
Comfrey has a tap-root, growing about 18 inches deep in the soil. It does a great job of breaking up compacted ground, accessing the minerals and nutrients out of reach of shallower plant roots. For this reason, comfrey leaves are a great addition to the compost pile, as those deep-seated nutrients of the ground are now taken up by the roots to be stored in the comfrey leaves. Once the microbes in the compost pile break down the comfrey leaves into its basic chemical elements, the nutrients are released into the compost and made available for use by other plants. Just don’t put any of those spreading roots into the compost pile. Keep any seeds out of the compost also.
So heed those enticing words on the plant labels when the just mention the words, ‘fast grower’ or ‘spreading’. Sometimes they really mean it!