Rhubarb is a perennial vegetable, though it is generally used as a fruit in desserts and jams. Here’s how to plant, grow, and harvest your own rhubarb.
Of the rhubarb plant, only the stalks are eaten. These have a rich, tart flavor. The leaves of the rhubarb plant are poisonous, so be sure that they are not ingested. Rhubarb is easy to grow, but needs cool weather to thrive.
The plant is a popular addition to backyard gardens and easy to grow (even difficult to get rid of when you want to). It requires a cold winter to thrive and produces its familiar brilliantly colored stalks—ranging from red to pink to pale green—in the spring.
Rhubarb is usually sold by the pound, ranging from $1.50 to $4 per pound. The price usually depends on availability from the season’s harvest.
Cultivation
Although rhubarb prefers a sunny spot, it will grow well in a lightly shaded position.
As rhubarb is a long-term crop, prepare the soil well before planting, to ensure good yields of tasty rhubarb sticks over several years. Dig over the soil to a good depth, adding lots of well-rotted manure or compost. Drainage is important, but lots of moisture is needed for a good crop – especially during dry summers. As the plants will remain in the ground for a number of years, remove all perennial weeds.
How to Grow By You
Once plants sprout, apply mulch to retain soil moisture and smother weeds. Renew mulch when the foliage dies down in fall to protect roots from extremely hard freezes. Provide enough water to keep roots from drying out, even when they’re dormant. Side dress with compost in midsummer and again in fall. Remove flower stalks before they bloom to encourage leaf-stalk production. After several years, when plants become crowded and the leaf stalks are thin, dig up the roots in spring just as they sprout. Divide so that each crown has one to three eyes (buds); replant.
Diseases
Rhubarb is usually pest free. Occasionally it’s attacked by European corn borers and cabbage worms. A more likely pest is rhubarb curculio, a ¾-inch-long, rust-colored beetle that you can easily control by hand picking. To destroy its eggs, remove and destroy any nearby wild dock in July.
Diseases also rare, but rhubarb can succumb to Verticillium wilt, which yellows leaves early in the season and can wilt whole plants in late attacks. Crown rot occurs in shady, soggy soil. For either disease, remove and destroy infected plants; keep stalks thinned to promote good air circulation, and clean up thoroughly around crowns in fall. If stands become seriously diseased, destroy the entire stand. Replant disease-free stock in a new location. ‘MacDonald’ is a rot-resistant variety that grows well in heavy soils.
How to Harvest
- Do not harvest any stalks during the first growing season so that your plants can become established.
- Harvest the stalks when they are 12 to 18 inches long. Usually after 3 years, the harvest period runs 8 to 10 weeks long. If the stalks become thin, stop harvesting; this means the plant’s food reserves are low.
- Grab the base of the stalk and pull it away from the plant with a gentle twist. If this doesn’t work, you can cut the stalk at the base. Be sure to discard of the leaves!
- Always leave at least 2 stalks per plant to ensure continued production. You may have a bountiful harvest for up to 20 years without having to replace your rhubarb plants.
- After harvest time, the stems may die back. Just remove all plant debris. Once your ground freezes, it’s best to cover rhubarb with 2 to 4 inches of mulch, preferably well-rotted compost; by adding nitrogen to the soil, you’re preparing the rhubarb plants for a good spring season.
Varieties
Many varieties of rhubarb exist, including some with green stalks that are surprisingly sweet. There are two basic types of rhubarb found in markets and larger grocery stores: the older, traditional variety with thicker, greener stalks, and the more intensely colored, slender-stalked variety, sometimes called hothouse rhubarb. The deep red stalks certainly make for brighter, more attractive dishes, but the concentrated color indicates stronger tartness. The greener stalks have a nicely balanced, mellow flavor.