Liliac de vara parfumat - Buddleja davidii 'Nanhoensis' (Butterfly Bush)

Buddleja davidii 'Nanhoensis' , also known as the 'butterfly bush' or 'summer lilac', is a compact cultivar of the species Buddleja davidii in the Scrophulariaceae family. This deciduous shrub is prized for its fragrant, vibrant purple-blue flowers and its small size, making it ideal for small gardens or containers. Originally from China, 'Nanhoensis' attracts butterflies and other pollinators, making it an excellent choice for ornamental landscapes.

Appearance of leaves, flowers and fruits

• Leaves : The leaves are lanceolate, dark green on the front and silver-gray on the back, with a slightly velvety texture, 8-15 cm long. They are smaller than those of other varieties, arranged oppositely on the branches, and fall in autumn without significant colors.
• Flowers : The flowers are small, tubular, grouped in compact, conical panicles , 10-20 cm long, of a deep purple-blue color with an orange center. They appear from July to September , emitting a sweet, floral fragrance , which attracts butterflies, bees and moths. Flowering can be prolonged by removing wilted flowers.
• Fruit : The fruit is a small, brown, ornamentally insignificant capsule containing fine seeds. In some regions, the seeds may contribute to the invasive spread of the plant.
• Fragrance : The floral, sweet and attractive fragrance is a strong point, being more pronounced on warm days.

Growth characteristics

• Height and width : Grows as a dwarf shrub, reaching 1-1.5 meters tall and 1-1.2 meters wide , with fine, arching branches, forming a rounded, dense crown.
• Vigor : It has moderate growth, being less expansive than other cultivars, which makes it ideal for confined spaces.
• Type : It is a deciduous shrub, with multiple stems, which produces few shoots from the root, maintaining a tidy shape.

Growing conditions

• Exposure : Prefers full sun for maximum flowering, but tolerates partial shade , with a reduction in the number of flowers. A sunny and well-ventilated location prevents diseases.
• Soil : Adapts to most soil types, preferring fertile, well-drained soil with a neutral or slightly alkaline pH (6-7.5). Tolerates poor or calcareous soils, but drainage is essential.
• Watering : Needs regular watering in the first few years and during dry periods, but once established, tolerates moderate drought well. Avoid soggy soils.
• Pollination : Flowers attract numerous pollinators, especially butterflies, contributing to the biodiversity of the garden.

Care and resistance

• Hardiness : It is resistant to temperatures down to -20°C (zones 5-9), making it suitable for temperate climates, including Romania. Young branches may be affected by late frosts, but the plant regenerates quickly.
• Fertilization : Apply a balanced fertilizer (e.g. 10-10-10) in early spring to stimulate growth and flowering. Avoid excess nitrogen, which favors foliage over flowers.
• Pruning : Prune severely in February-March , reducing branches to 20-30 cm from the ground, to stimulate abundant flowering and maintain a compact shape. Remove faded flowers during the summer to prolong flowering.
• Pests and diseases : May be affected by mites, aphids or powdery mildew in humid conditions. Good ventilation and avoiding wetting the leaves will prevent problems.
• Invasiveness : Buddleja davidii can become invasive in some regions due to wind-borne seeds. Removing spent flowers reduces this risk.
• Fauna : It is a magnet for butterflies, bees and moths, making it an essential plant for gardens that support biodiversity.

Use

Buddleja davidii 'Nanhoensis' is ideal for small gardens , mixed borders , patio containers or as an accent plant in cottage or modern landscapes. The purple-blue flowers combine beautifully with plants such as lavender, sage or white roses. Due to its compact size, it is perfect for small spaces or planters, providing vibrant colour and attracting pollinators.

Origin

Buddleja davidii is native to China , where it grows in rocky areas and on river banks. The cultivar 'Nanhoensis' was selected for its dwarf stature and compact flowers, and was introduced into horticulture as part of the Nanho series, which includes smaller, neater varieties. It is valued for its adaptability and elegant appearance.