Erysimum, commonly known as Wallflower, is a popular garden plant celebrated for its fragrant, vibrant blooms and adaptability. These plants offer a spectrum of colors, including yellow, orange, pink, purple, and red, attracting pollinators like bees and butterflies with their delightful scent. Wallflowers can be annuals, biennials, or short-lived perennials, providing continuous color from early spring into summer, with some varieties blooming into autumn. Their resilience makes them a favored choice for lasting floral display.
Planting Erysimum
Successful Erysimum planting begins with site selection and soil preparation. Wallflowers thrive in full sun (at least six hours daily), though they tolerate partial shade in hotter climates. Good drainage is paramount for these plants, as they are susceptible to root rot in overly wet conditions.
Ensure the soil is well-draining, potentially amending heavy or clay soils with organic matter like compost to improve structure and fertility. Wallflowers prefer a neutral to slightly alkaline soil pH (6.5-8.0). Optimal planting times are spring or fall, allowing roots to establish before extreme temperatures. When planting, dig a hole slightly larger than the root ball, place the plant at the same depth as its container, and space plants 12 to 18 inches apart for proper air circulation. After planting, backfill and water thoroughly to settle the soil.
Erysimum Care Essentials
Consistent care ensures Erysimum plants remain healthy and produce abundant blooms. While they enjoy bright conditions, wallflowers tolerate some afternoon shade in regions with intense summer heat. Their preference for well-drained soil means avoiding overwatering.
Once established, Erysimum exhibits good drought tolerance, making them suitable for water-wise gardens. During prolonged dry spells or the growing season, moderate watering promotes healthier growth and more prolific flowering. Wallflowers are not heavy feeders and generally do not require extensive fertilization. A light application of a balanced, slow-release fertilizer in early spring provides sufficient nutrients.
Pruning and Maintenance
Regular pruning and maintenance encourage continuous blooming and maintain the plant’s shape. Deadheading spent flowers prevents the plant from expending energy on seed production, redirecting it towards new blooms. This extends the flowering period.
Beyond deadheading, light pruning helps maintain a compact, bushy form and prevents leggy growth. For perennial Erysimum, a light trim of 2-5 cm of top growth in late winter or early spring rejuvenates the plant and promotes bushier growth. If stems become woody, a more substantial cut back to a new shoot or leaf spur may be necessary, though this should be done carefully.
Common Erysimum Challenges
While generally robust, Erysimum can encounter issues, often linked to environmental conditions. Root rot is a common problem, primarily caused by overly wet or poorly draining soil, avoidable with proper soil preparation and careful watering. Fungal diseases like powdery mildew can occur, especially with poor air circulation or excessive moisture. Adequate spacing helps mitigate this.
Pests such as aphids, flea beetles, and slugs or snails may occasionally affect Erysimum. Aphids can be managed with insecticidal soap. Flea beetles create small holes in leaves, though established plants are usually not severely damaged. Slugs and snails feed on foliage, indicated by ragged holes. Proper garden hygiene, including removing plant debris, helps deter these pests.