Dendrobium deflexum

General Information

Dendrobium deflexum is a large sympodial cool to warm growing epiphytic, lithophytic or terrestrial orchid belonging to the sub family Epidendroideae.

Plant Description

Sympodial. Grows to 3.6-25cm. Each new growth has numerous thick leaves that grow to 1.8-2.3cm long. Pseudobulbs grow to 1.8-2.3cm

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 wet-dry cycle between waterings, they should be watered frequently but only when the moisture is approaching dryness, where the pot feels light and/or the media looks dry. Keep an eye on mounted orchids in warm weather as they may dehydrate quickly.

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 can be sensitive to repotting though should not require repotting regularly. Repotting should be done when the mix has broken down to the point that it doesn't absorb water or holds onto water for far too long, usually the plant shows a decline in growth as well.

The mix should be free draining, with a blend of 30% inorganic ingredients such as coarse sand, gravel or perlite, mixed in with about 70% organic ingredients such as peat, leaf litter or decomposed bark. Avoid commercial potting mixes as they can vary wildly and may contain "wetting agents" that can hold onto water for loo long, causing rotting and stunted growth.