Bujori de gradina parfumati - Paeonia lactiflora 'Karl Rosenfield'

Paeonia lactiflora 'Karl Rosenfield' is a classic variety of herbaceous peony, renowned for its large, double flowers of intense ruby red and its robust and elegant appearance. This perennial plant is one of the most popular choices in ornamental gardens due to its vibrant color and impressive presence.

Flower Appearance

• Shape: The flowers are double, with numerous overlapping petals that create a round, full shape resembling a globe. The flower diameter can reach 15-18 cm.
• Color: They have a deep shade of ruby red or crimson red, sometimes with darker accents toward the center, maintaining their intensity throughout the blooming period. Unlike other varieties, they do not fade significantly.
• Fragrance: It emits a sweet, subtle fragrance, typical of Paeonia lactiflora peonies, adding extra appeal.
• Blooming period: Blooms in May-June, with each flower lasting about 7-10 days. The plant produces several flowers successively, extending the floral display over several weeks.

Growth Characteristics

• Height: Grows up to 80-100 cm tall and about 70-90 cm wide, forming a dense and well-structured bush.
• Foliage: The leaves are a dark, glossy green, deeply lobed, providing a beautiful contrast with the red flowers. The foliage remains decorative throughout the season, sometimes acquiring reddish hues in autumn.
• Vigor: It is a vigorous plant with strong stems that support the heavy flowers well, although in conditions of heavy rain or wind it may require support (e.g., rings or stakes).

Growing Conditions

• Exposure: Prefers full sun or light partial shade, with at least 6 hours of daily light for optimal flowering.
• Soil: Requires fertile, well-drained soil, with a neutral to slightly acidic pH (6-7). Soils rich in organic matter, such as clay soils, are ideal.
• Watering: Needs regular watering, especially in the first year and during dry periods, but does not tolerate excess moisture or waterlogged soils.
• Planting: Plant in autumn (September-October) or early spring, with the rhizome no more than 2-3 cm below soil level to ensure flowering.
• Pruning: In autumn, after the leaves dry, cut the stems 5-10 cm above the ground.

Care and Resistance

• Hardiness: Extremely cold-hardy, tolerating temperatures down to -30°C (USDA zones 3-8), making it suitable for temperate climates, including Romania.
• Fertilization: A balanced fertilizer (e.g., 10-10-10) applied in spring at shoot emergence stimulates flowering. Avoid excess nitrogen to prevent promoting foliage over flowers.
• Pests and diseases: Resistant to most issues but can be affected by gray mold (Botrytis) in damp, poorly ventilated conditions; ensure good air circulation.

Origin

Paeonia lactiflora, the base species, is native to East Asia, especially China, Mongolia, and Siberia, where it naturally grows in meadows and mountainous areas. Cultivated in China for over 2,000 years, initially for its medicinal properties, it later became an ornamental symbol. The 'Karl Rosenfield' Peony variety was introduced in 1908 by American breeder John Rosenfield, who named the plant after himself. It is the result of selective crosses of lactiflora peonies aimed at producing a double flower of intense red that holds up well in gardens. Since then, it has remained one of the most beloved peony varieties worldwide.