One of spring’s garden harbingers, rhubarb stems burst through soil early in the growing season. The tart, colorful stems grace pies and jams with tangy flavor that is typically tamed with sugar or teamed with sweet strawberries. Rhubarb adds sculptural beauty to the garden with its blocky stems and large leaves. While leaves offer textural beauty, they’re not part of the harvest package. Rhubarb leaves contain high concentrations of oxalic acid and shouldn’t be eaten. When growing rhubarb, harvest the stems, then remove leaves and add them to the compost pile. Rhubarb grows best in zones where the ground freezes in winter. Plants require an extended chilling period with temperatures below 40 degrees to produce a crop of stems. As a result, rhubarb is commonplace in gardens throughout the coldest sections of the country, although it can be grown as far south as zone 7.
Quick Guide to Growing Rhubarb
- Plant rhubarb during the cool days of early spring, once the ground thaws.
- Rhubarb produces a harvest for up to 8 years, so grow it in a sunny area where it will go undisturbed for a long time.
- Give rhubarb room to spread out by planting them 4 to 6 feet apart.
- Improve your native soil by mixing in several inches of aged compost or other rich organic matter.
- When hot weather arrives, apply a 2-inch layer of mulch to keep soil moist and help block weeds.
- Check soil moisture regularly and water when the top inch of soil becomes dry.
- Feed rhubarb regularly with a continuous-release plant food.
- Start regular harvesting in year 3 when stalks are 12 to 18 inches long and reach their ideal red color.