Paeonia lactiflora possesses a distinct growth habit and foliage texture that can be enhanced by contrasting companions. Its lush, deep green, divided leaves form a substantial mound that dies back in winter. To complement this, consider plants with fine, airy, or vertical foliage. The feathery plumes of Astilbe species or the delicate, fern-like leaves of Artemisia 'Powis Castle' provide a soft textural contrast that makes the peony's foliage appear even more robust. For vertical form, the sturdy, sword-like leaves of Iris germanica (Bearded Iris) create a strong architectural counterpoint, especially effective before the peonies bloom. These combinations ensure visual interest even when the peonies are not in flower.
The spectacular but fleeting bloom of Paeonia lactiflora in late spring to early summer necessitates companions that provide flowers before, during, and after its display. Early spring bulbs like Narcissus (Daffodils) or Tulips emerge and bloom before the peony's foliage is fully developed, utilizing the space efficiently. As the peony's flowers fade, mid-to-late summer bloomers take the stage. Perennials such as Phlox paniculata (Garden Phlox), with its domed clusters of flowers, and Hemerocallis (Daylilies) extend the color show. For late summer and autumn interest, Sedum 'Autumn Joy' provides flat, nectar-rich flower heads that contrast beautifully with the peony's seed pods.
Selecting plants with complementary or harmonious color palettes is crucial. The wide range of Paeonia lactiflora colors dictates different pairings. White or soft pink peonies pair elegantly with the violet-blue spires of Salvia nemorosa (Wood Sage) or Nepeta (Catmint). Bold red or deep pink peonies can be balanced with the softer hues of Geranium 'Rozanne' or Alchemilla mollis (Lady's Mantle), whose lime-green flowers act as a neutral buffer. Scale is equally important; avoid planting low-growing, delicate plants directly against a large peony bush, as they may be overshadowed. Instead, place medium-height perennials like Allium giganteum (Ornamental Onion) or Campanula persicifolia (Peach-Leaved Bellflower) nearby to create a layered effect.
Companion planting from an ecological perspective involves choosing species that support the peony's health without competing excessively for resources. Many suitable companions, such as Nepeta and Salvia, are drought-tolerant once established, matching the peony's preference for well-drained soil and reducing the need for excessive watering. Furthermore, these plants are excellent for attracting pollinators like bees and beneficial insects to the garden, which helps create a balanced ecosystem. It is vital to avoid aggressive spreaders or deeply rooting shrubs that might compete with the peony's dense, fleshy root system for water and nutrients.
