Dendrobium compactum

Also known as: The Compact Dendrobium or Dendrobium wilmsianum in the subfamily: Epidendroideae

Native to: China Thailand

General Information

The Compact Dendrobium is a sympodial cool to warm growing epiphytic orchid belonging to the sub family Epidendroideae native to China and Thailand.

Plant Description

Sympodial. Grows to 9cm. Each new growth has numerous leaves that grow to 4-8cm long. Pseudobulbs grow to 3-8cm

Care Notes

These orchids live in environments that receive constant moisture, high humidity, and are surrounded by other plants such as ferns and mosses which not only attract moisture but compete for it as well.

As a consequence they can be difficult to keep healthy in an artificial environment where a constant balance has to be maintained between providing constant moisture to the roots, but also allowing them to not become soggy and dry quickly as they would in the wild. For this reason it's important to take into account the size of the plant, the health and fragility of the root system, and also think about your watering habits. If you water frequently you can use a media that drains more freely, if you water less reliably you will need to find a media that offers retention and keeps humidity around the roots without being soggy.

Because these orchids like high amounts of water, other plants such as ferns and weeds may start to grow alongside the orchid, whose roots can make the media quite dense, effectively strangling the orchid's roots, it's best to pluck them out before they become a problem. Fungus and bacteria can be an issue as well, but usually are a sign of overwatering, smell the media occasionally to check, and increase airflow, reduce watering, and adjust temperatures accordingly (often bacteria only flourish in warmer temperatures, fungus less so). 

 

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 low to high elevations. Rainfall ranges from 8mm to 292mm per day, heaviest in September and lightest in January. Humidity ranges from 58% to 83%, highest in August and lowest in March. Temperature ranges from 6C to 28C, highest in April (17C to 28C) and lowest in January (6C to 22C).

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

Fertiliser

dormant-medium-demand-orchid Apply fertiliser regularly at half strength year round. Use a high Nitrogen fertiliser during Spring and Summer. Use a high Phosphorous fertiliser during Summer.

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,