When to Split Rhubarb Plants?

Rhubarb (Rheum rhabarbarum) is a vegetable used for making pies, pastries, jams and sauces. Two sweet varieties are Canada Red and Valentine. The plant is perennial and lives for at least five years. You may notice smaller leaves and sprouting seed stalks when your rhubarb garden becomes too crowded. You can relieve the crowding and propagate new plants by splitting them.

Split only mature rhubarb plants, from three to five years old, that have produced a full harvest. Younger plants need their stored nutrition for growth. Additionally, if excessive seeding was a problem with some of the rhubarb plants in your garden last year, then do not select those particular plants for splitting. Better-quality plants tend to sprout fewer seed stalks, according to the University of Illinois Extension.

Split rhubarb when the plant is dormant. A good time is in early spring, before the last frost date for your area. The U.S. Department of Agriculture publishes last frost dates for all regions of the country.

One way to propagate rhubarb is by splitting the crown into two, three or four pieces. Cut the crown in half. If each piece has at least two roots with buds, split each half into two pieces. Transplant the rhubarb into its new place in the garden.

Splitting the roots is another way to increase the number of rhubarb plants. Dig up the roots and identify the buds. Cut the roots so that each piece has one or two buds. You should get from four to eight cuttings, depending on the number of strong buds.