Grammatophyllum speciosum

Also known as: The Showy Flowered Grammatophyllum or Grammatophyllum macranthum Grammatophyllum fastuosum Grammatophyllum giganteum Pattonia macrantha Grammatophyllum sanderianum In Thailand - Hang chang - Ueang phetchahueng - Wan phetchahueng in the subfamily: Epidendroideae

Native to: Indonesia Thailand

General Information

The Showy Flowered Grammatophyllum is a large hot growing epiphytic or lithophytic orchid belonging to the sub family Epidendroideae native to Indonesia and Thailand.

Plant Description

Grows to 300-2100cm. Each new growth has numerous erect leaves that grow to 2.4-70cm long. Pseudobulbs grow to 0.4-300cm

Substrate(s)

• Coarse
• Medium
• Bark
• Charcoal
• Perlite

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

Grows at low to high elevations. Rainfall ranges from 165mm to 389mm per day, heaviest in November and lightest in July. Humidity ranges from 79% to 87%, highest in October and lowest in July. Temperature ranges from 21C to 30C, highest in May (22C to 30C) and lowest in January (21C to 28C).

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.

Fertiliser

These plants thrive on fertiliser, especially during periods of growth. Liquid fertiliser can be applied year round at the recommended strength, augmented with manure pellets or other quickly degradable fertiliser, applied away from the base of the plant, during periods of strong growth. Slow release pellets can also be applied year round at the rate of 2-3 pellets per cup (250ml) of media.

They can benefit from a high phosphate fertiliser leading up to flowering season, and by a high nitrogen fertiliser when new growth appears. 

Fertiliser can be applied heavily year round. Use a high Nitrogen fertiliser during Spring and Summer. Use a high Phosphorous fertiliser during Summer. Reduce fertiliser when plant is dormant.

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,

Use water retentive media such as moss to prevent roots from drying out quickly This plant does very well in baskets or suspended pots Repotting is best done annually.