Roots on Roots

Enlarge Image Image Gallery Need more comfrey? Take a shovel to a healthy plant and dig around the root zone. The thick, fleshy roots are the ones you’re after. Photography by J. G. Strauch, Jr.

HAVE YOU EVER TRIED to get all the bindweed or gout­weed—or mint—out of your herb bed, only to discover new plants flourishing a few weeks later? All that hoeing and digging you did just chopped up the roots and rhizomes, and each bit turned into a new plant. Aggravating as this tendency can be when you’re trying to get rid of an unwanted plant, it can be turned to your advantage to multiply desirable herbs.

Herbs that have fleshy roots or that tend to produce suckers are good candidates for this kind of propagation. They include bayberry, sassafras, horehound, bee balm, butterfly weed, purple coneflower, violets, salvias, sea holly, perennial mullein, Oriental poppies, and sea lavender. Root cuttings can give you more plants than division, and the technique is easier than stem cuttings, at least for many herbs. Vegetative propagation using root cuttings is an especially useful method for increasing prized cultivars or hybrids that don’t come true from seed.

Taking cuttings

Comfrey is a fine choice for your first attempt at this technique, as the root pieces readily form roots and tops. For the greatest likelihood of success, take root cuttings early this spring before the plant has put out a lot of new top growth or or early next fall after flowering is done. When the plant is putting its energy into flower production, stem buds form less readily in the root tissue. Even so, most of the root cuttings of comfrey that I took late last spring when the plant was several feet tall showed new top growth within five weeks.

Taking cuttings from large roots takes less dexterity and fussing than with stem cuttings. You can dig up an established comfrey plant (or other herb) and cut off roots with pruning shears or a sharp knife, or leave the plant in the ground and just dig up soil next to it that contains some of the larger roots.

You are after the fleshy roots 1/4 to 1/2 inch thick, not the fine feeder roots. Cut these thick roots into 2-inch lengths and gather several together with a rubber band to keep them oriented in the same way that they grew. You can cut the tops of the pieces straight across and the bottoms diagonally to help you recognize which end is which, but the plant needs no such reminders. The end of the root piece that was originally uppermost will sprout a stem and leaves, and the opposite end will sprout roots, no matter how it is planted, but orienting the piece correctly enables it to expend the least amount of energy in sprouting.