Strophanthus LUTEOLUS

Strophanthus LUTEOLUS - Yellowish strophanthus, Strophanthus luteolus.

Strophanthus is a genus of climbing shrubs and lianas in the dogbane family (Apocynaceae), comprising more than 35 species distributed in tropical regions of Africa and Madagascar. These plants are distinguished by strong, flexible stems that often reach significant lengths, and thin, leathery leaves arranged oppositely or with a slight spiral deviation. Large flowers of whimsical shape with long thread-like appendages on the petals give the genus particular ornamental value.

Strophanthus flowers are white, cream, yellow, or pinkish, often with contrasting patterns. They feature characteristic elongated corolla lobes that can hang down or twist into a spiral. The fruits consist of two long follicles containing numerous seeds with a silky tuft that aids in wind dispersal. Many species of the genus have long been known for their rich content of cardiotonic compounds.

Strophanthus luteolus is a perennial liana native to tropical regions of Africa, particularly in the eastern and central parts of the continent. Long, slender shoots can twine around trees and other supports. The leaves are opposite, oval or lanceolate, with a smooth surface. The flowers are showy, with long narrow petals, often twisted or elongated in the form of 'tails' characteristic of the genus. The flowers have a yellowish coloration, sometimes with purple or brown spots.

The seeds are large, about 10 mm (0.4 in) long, oblong, light brown, equipped with a long silky tuft that aids in wind dispersal. Germination is usually stable - around 60-75%.

Before sowing, the seeds are soaked for 12 hours in warm water or a mild growth stimulant solution. Sowing is carried out in a light substrate of peat and sand or leaf mold and perlite, with seeds buried 5-8 mm (0.2-0.3 in) deep with the tail pointing upwards. The plantings are placed in a mini-greenhouse or covered with film and germinated in bright light, but not direct sun, at a temperature of 24-28 °C (75-82 °F). Stable moisture is maintained, and daily airing is conducted.

Sprouts appear on average after 15-25 days, with a minimum period of about 10 days and a maximum possible period of more than 40 days. After a pair of true leaves appears, young plants are carefully transplanted into individual pots. The plant can also be propagated by semi-lignified cuttings, but rooting requires greenhouse conditions and high air humidity.

© Greeniverse. All rights reserved.

Strophanthus prefers bright diffused light and warm conditions. The optimal temperature during the period of active growth is 22-28 °C (72-82 °F). Direct midday rays can cause burns, so light shading is required. In winter, the plant requires a cooler regime - around 12-15 °C (54-59 °F); partial or complete leaf fall is possible during this period, which is normal for the genus. In spring, as temperatures rise and day length increases, the plant leafs out again.

Watering is done moderately: the substrate should dry slightly in the upper layer between waterings. Water stagnation is excluded, as the roots are sensitive to waterlogging. In winter, watering is reduced to a minimum. During warm periods, it is beneficial to periodically mist the leaves or provide increased air humidity, especially in hot weather.

Strophanthus requires a light, breathable substrate - a mixture of leaf mold with the addition of sand, perlite, or coconut coir. A suitable soil reaction is neutral or slightly acidic. Fertilizer applications are made every two weeks during the period of active growth, primarily with balanced mineral fertilizers.

Most species require a support - a trellis, netting, or taut guide wires, since the shoots are climbing and elongate rapidly. The plant's sap is toxic, so all work, including pruning and repotting, must be performed wearing gloves.