Dendrobium vannouhuysii

Also known as: Vannouhuys' Dendrobium or Dendrobium vannouhuysii var. rhombipetalum Dendrobium vannouhuysii var. vannouhuysii in the subfamily: Epidendroideae

General Information

Vannouhuys' Dendrobium is a sympodial cold to warm growing epiphytic orchid belonging to the sub family Epidendroideae.

Plant Description

Sympodial. Grows to 4.5cm. Each new growth has numerous oblong shaped leaves that grow to 0.8-1.1cm long. Pseudobulbs grow to 4.5cm. The plant tends to climb or sprawl with each new growth

Substrate(s)

• Coarse

Care Notes

These orchids like to be watered regulary, especially during warm weather, and prefer a well draining mix or also do well mounted, provided they can be watered daily or even many times a day.

These are quite a forgiving orchid, there are no special requirements to get this orchid to flower, just good care and consistent conditions. Larger plants may be more fussy and can react poorly to change; a poorly timed repotting, a pest infection or an unusually hot day can set them back for a couple of years. However, even plants that have been treated poorly can thrive, and if they are set back they often recover much stronger then they would otherwise be.

Climate

The orchids are well adapted for hot weather, accompanied by sporadic, unpredictable rainfall and a generally dry climate. They can tolerate a lot of neglect as they are quite used to it, however they can be prone to underwatering and may collapse in cold, wet weather.

For this reason it's best to dedicate a sheltered, protected area for them where the watering can be controlled, such as a corner of a greenhouse or in a sheltered balcony. They can also do well hung near the roof of a shadehouse or sheltered greenhouse where they receive the extra heat but not as much water as other plants. 

Grows at high elevations. Rainfall ranges from 48mm to 175mm per day, heaviest in September and lightest in February. Temperature ranges from 10C to 21C, highest in October (13C to 21C) and lowest in January (10C to 18C).

Watering

These orchids prefer a constant supply of moisture, with a slight drying out between waterings. Saucers can be placed under pots to retain moisture during hot weather, however the saucers should be removed or let to dry every 1-2 weeks to prevent rot. Keep an eye on the plant especially in hot weather and look for cues of under/overwatering and adjust accordingly.

Keep moisture levels up during hot weather as the plant is prone to dehydration Be sure to provide strong air circulation after watering to prevent fungal and bacterial infections from water sitting on leaves.

Fertiliser

Apply liquid based fertiliser per recommended directions. They can benefit from a high phosphate fertiliser leading up to flowering season, followed by a high nitrogen fertiliser when new growth appears, and a balanced fertiliser in other times. These orchids can also tolerate slow release fertiliser applied 1-2 pellets per cup (250ml) of media.

Use balanced fertiliser year round. Apply fertiliser regularly at half strength year round.

Potting

These plants are quite forgiving and will do well repotted ever 2-3 years. The mix should be coarse, well draining, and allow space for air to move and for roots to grow. 

Alternatively, these plants will also do well mounted to tree fern or cork slabs, or mounted to trees.

Best time for repotting or mounting the orchids is the end of winter when new growths start to appear. Avoid repotting during hot weather,

This plant does well mounted to Cork slabs or Stone slabs.