Peonies (Paeonia spp.) are perennial plants known for their large, showy blooms. However, their heavy flowers can cause stems to bend or break, especially after rain or strong winds. To support peony blooms effectively, it's essential to understand their growth habits. Peonies develop thick, woody stems, but the weight of their blooms—particularly in double-flowered varieties—can exceed the stem's strength. Additionally, peonies grow in clumps, with new shoots emerging from underground buds (called "eyes") each spring.
Selecting peony varieties with stronger stems can reduce the need for additional support. Single or semi-double peony blooms (e.g., Paeonia lactiflora 'Krinkled White') are lighter than fully double varieties (e.g., 'Sarah Bernhardt'). Tree peonies (Paeonia suffruticosa) have sturdier woody stems, while herbaceous peonies (Paeonia lactiflora) often require more support. Researching and planting naturally robust varieties is the first step in minimizing bloom droop.
Planting peonies correctly ensures a strong foundation for their blooms. Place peony roots in well-draining soil with the "eyes" no deeper than 2 inches below the surface—planting too deep weakens stems. Space plants at least 3 feet apart to allow air circulation and prevent overcrowding, which can lead to weaker stems. Amend the soil with compost to promote healthy root development, indirectly supporting stem strength.
Installing supports early in the growing season is crucial. Peony rings or grids (often made of metal or plastic) are placed around the plant as stems emerge. These supports should be sturdy and tall enough to hold the mature plant. Alternatively, stake individual stems with bamboo sticks and soft ties, ensuring ties don’t cut into the stems. For larger clumps, tomato cages or custom-built frameworks can provide reliable support.
Pruning excess foliage and buds can reduce the weight on peony stems. Remove smaller side buds (disbudding) to direct energy into fewer, stronger blooms. Thin out crowded stems to improve air circulation and prevent fungal diseases that weaken plants. After blooming, deadhead spent flowers to prevent seed formation, which diverts energy from stem and root development.
Consistent watering and balanced fertilization promote sturdy stems. Water peonies deeply but infrequently to encourage deep root growth. Avoid high-nitrogen fertilizers, which can lead to overly lush, weak growth. Instead, use a low-nitrogen, high-phosphorus fertilizer (e.g., 5-10-5) in early spring to support root and stem strength. Mulching with compost also provides slow-release nutrients.
Environmental factors like wind, rain, and pests can weaken peony stems. Plant peonies in a sheltered location or use windbreaks to reduce stem stress. Monitor for pests like thrips or botrytis blight, which can damage stems. In rainy climates, consider temporary covers during heavy downpours to prevent waterlogged blooms from weighing down stems.
