Peonies are a beloved garden perennial, known for their abundant, showy flowers. Understanding the root system’s physical characteristics is necessary for successful planting, especially when using a bare root division. The root is the plant’s life source, holding the energy required for the next season’s growth and bloom. Knowing what a healthy root looks like ensures the plant has a strong start and will thrive in the landscape.
General Appearance of Peony Roots
The typical dormant herbaceous peony root is a dense, gnarly mass designed for nutrient storage. These large, tuberous structures function as underground pantries for the plant. The exterior of a healthy, mature root division is usually dark tan or brown.
If a root is cut, the interior tissue appears pale yellow or creamy white. This fleshy interior is packed with carbohydrates, which the plant uses to fuel spring growth and flower production. The texture of these storage roots is firm and brittle, especially if allowed to dry out before planting.
Essential Structural Components
A peony root division features specific anatomical components that dictate its planting position and future growth. The most identifiable feature is the crown, a thickened area where the storage roots converge and where previous stems met the subterranean structure. This junction is the point from which new growth originates annually.
Located on or near the crown are the eyes, which are small, reddish, pink, or white buds. These dormant buds contain the structures that will become next year’s stems, leaves, and flowers. A viable bare root division typically includes three to five visible eyes.
Successful planting depends on identifying the crown and positioning the eyes correctly, usually one to two inches below the soil surface. Attached to the main storage roots are thinner, fibrous roots necessary for absorbing water and minerals. These fine roots are important for the plant’s initial establishment.
Distinguishing Herbaceous and Tree Peony Roots
Peonies are categorized into two types with distinctly different root systems: herbaceous and tree peonies. Herbaceous peonies, the most common garden variety, have the fleshy, tuberous storage roots previously described, which die back to the ground each winter. Their root mass is clustered, with thick, non-woody tubers providing the bulk of the structure.
Tree peonies are woody shrubs that maintain above-ground stems year-round. When purchased, especially if grafted, the root structure often resembles a single, thick, carrot-like taproot. On a grafted tree peony, a visible graft union will be present—the slightly swollen or uneven point where the flowering cultivar was joined to the rootstock.
Identifying Healthy Root Stock
A visual inspection of a bare root division before planting offers the best indication of its quality and viability. A healthy peony root should feel firm and solid to the touch, indicating good moisture and carbohydrate reserves. The root should be clean, with a dark tan or brown exterior color.
Avoid roots that feel soft, mushy, or have large black areas, as these are signs of fungal infection or root rot caused by excessive moisture. Conversely, roots that are shriveled, wrinkled, or brittle suggest the plant has lost too much water during storage and may struggle to establish. The visible eyes should appear plump and firm, not desiccated, offering a clear sign of the plant’s readiness to grow.