Rhubarb is a long-lived perennial plant, often treated as a fruit due to its tart, edible stalks. While growing rhubarb from seed is possible, it is slow and often results in unpredictable characteristics. The most effective method for establishing a thriving patch is by planting dormant root divisions, known as crowns. These crowns are segments of the mature root system containing several buds, ensuring the new plant is genetically identical to the parent.
Preparing the Planting Site
Selecting the correct location is important because rhubarb plants can remain productive in the same spot for over a decade. Rhubarb thrives in full sun but can tolerate light shade. It requires adequate space, as mature plants can spread up to five feet wide. The ideal time to plant crowns is in early spring as soon as the soil is workable, or in late fall after the plants have entered dormancy.
Rhubarb demands fertile, well-draining soil to prevent the crowns from rotting. Soil preparation should focus on deep cultivation, loosening the earth to a depth of at least 10 inches to accommodate the extensive root system. Before planting, thoroughly incorporate generous amounts of organic matter, such as well-rotted compost or aged manure, into the soil. This material improves drainage and provides necessary nutrients for this heavy-feeding plant.
Step-by-Step Crown Installation
Begin by digging a hole substantially wider than the crown’s root mass and deep enough for correct positioning. If planting multiple crowns, space them at least three feet apart. Adequate spacing is crucial, as rhubarb becomes a large, leafy plant requiring considerable room to spread.
Place the crown into the prepared hole, ensuring the buds, or “eyes,” face upward toward the soil surface. Precise planting depth is important, as planting too deeply can delay or prevent establishment. Cover the crown with soil so the top of the eye is only about one to two inches below the soil line.
Gently firm the soil around the crown to eliminate air pockets and provide good contact between the roots and the earth. Immediately after planting, give the newly installed crowns a thorough watering to settle the soil and hydrate the roots. This helps the plant transition from its dormant state.
Establishing the Rhubarb: First-Year Care
Following installation, the focus of the first year is entirely on root development to ensure a long-lived, productive patch. The newly planted crowns require consistent moisture, especially during dry periods, to encourage a robust root system. While the soil should be kept moist, it must never become waterlogged, as this can quickly lead to crown rot.
Weeds must be managed aggressively around the young plants, as they compete directly for water and soil nutrients. Applying a two to three-inch layer of organic mulch, such as straw or shredded leaves, helps suppress weeds and conserve soil moisture. The most important rule for the first growing season is the prohibition against harvesting any stalks.
The energy generated by the leaves in the first year must be channeled back into the root system to build up reserves for future production. Pulling stalks prematurely depletes these reserves, weakening the plant and resulting in a less productive patch later. Allowing the foliage to grow unimpeded until the first hard frost ensures maximum energy is stored in the crown for the following spring.