Read more of cultivation of Aerangis arachnopus (Rchb.f.) Schltr.
Culture:
Light:
1500-2300 fc. Light should be filtered or diffused, and plants should not be exposed to direct midday sun. Strong air movement should be provided at all times. Growers report that plants should be grown in moderate shade.
Temperatures:
Summer days average 85-86F (29-30C), and nights average 68F (20C), with a diurnal range of 17-18F (9-10C).
Humidity:
80-85% most of the year, dropping to near 75% for about 2 months in late winter and early spring.
Water:
Rainfall in the habitat is heavy most of the year, with 2-3 rather dry months in winter. Cultivated plants should be watered heavily while actively growing. Water should be reduced somewhat in late autumn.
Fertilizer:
1/4-1/2 recommended strength, applied weekly when plants are actively growing. Many growers prefer to use a balanced fertilizer throughout the year; but others use a high-nitrogen fertilizer from spring to midsummer, then switch to one high in phosphates in late summer and autumn.
Rest period:
Winter days average 81-83F (27-28C), and nights average 64-66F (18-19C), with a diurnal range of 17-18F (9-10C). The range in habitat elevation indicates that plants should adapt to temperatures 6-8F (3-4C) cooler than indicated. Growers report that plants grow well in intermediate conditions, but may grow better under slightly warmer conditions. Rainfall in the region is lower in winter. In addition to the rainfall, however, moisture from heavy dew and late-night mist often is available to the plants, and this moisture is not reflected in the rainfall averages. Cultivated plants need less in winter, but they should never dry out completely or remain without water for long periods. In most growing areas, somewhat regular early-morning mistings between occasional light waterings should provide the dry rest without letting the plant become too dry. Fertilizer should be reduced or eliminated when water is reduced.
Growing media:
As with most Aerangis species, Aerangis arachnopus usually grows better and its pendent flower spikes are more easily displayed when plants are mounted on slabs of rough bark. Mounted plants need high humidity and must be watered or misted at least once a day, however, and during hot, dry weather they may require several waterings a day. For those growers that find it difficult to keep mounted plants moist enough, they may also be grown in small 3-5 in. (8-13 cm) hanging pots or baskets using a very coarse, open, fast-draining medium to anchor the plant but allowing the roots to wander outside the container. Plants should be repotted if the medium starts to break down. Repotting done just as new roots start to grow enables the plant to become reestablished in the shortest possible time. Hillerman and Holst (1986) reported that some Aerangis species seem to slowly dehydrate under normal misting or watering practices when grown on slabs. They indicated that if the leaves start to shrivel or wrinkle or show other signs of stress, the plant usually will recover and grow well if soaked in water for about 20 minutes at least 3 times a week.
Notes:
Growers report that cultivated plants bloom in summer.
References:
This information is quoted from a Charles and Margaret Baker culture sheet, with permission from Troy Meyers
