What are the latest growing conditions for Dendrobium officinale?

Dendrobium officinale is also known as Tiepi Lan, Tiediao Lan, Lishu Cao, and in Yunnan it is commonly called Heijie Cao. In China it is distributed in the mountainous areas of Anhui, Zhejiang, Yunnan, Guizhou, Sichuan and other places south of the Qinling Mountains and the Huai River, mainly growing on the cliffs and in the rock crevices of the high mountains and steep ridges of these regions. Due to the special nature of its growing conditions and the limited scope of its distribution, combined with long-term harvesting, its natural resources are on the verge of exhaustion and the domestic market supply is in short supply, so there are even stricter requirements for its growing environment.

Seedling production of Dendrobium officinale

Healthy, well-growing broad-leaf red-stem type Dendrobium officinale is collected in the wild as a seed source and carefully maintained. During the flowering season of Dendrobium officinale, artificial pollination is carried out to obtain authentic Dendrobium officinale seed pods. After the seeds mature, they are sown to form a mother flask of Dendrobium officinale, and through subculturing -> strengthening the seedlings -> rooting, a healthy and authentic mother flask of Dendrobium officinale is obtained.

Environmental conditions for Dendrobium officinale

Dendrobium officinale has relatively strict environmental requirements, and choosing a suitable environment is half the battle for successful cultivation. Dendrobium officinale should be planted in a humid and cool environment at an altitude of about 800-1600 m. The suitable growth temperature is 15-30°C, with 16-21°C being more suitable during the growing period, a nighttime temperature of 10-13°C, a day-night temperature difference maintained at 10-15°C, and a frost-free period of 250-300 days is optimal. The annual rainfall should be above 1000 mm. Seedlings are prone to freezing below 10°C, and generally Dendrobium officinale begins to shed leaves below 5°C. A relative humidity of around 80% is more suitable for Dendrobium officinale, and it should avoid dryness and waterlogging, especially when new buds begin to sprout and new roots form, when sufficient water is needed. In summer and autumn, shading of 70% is appropriate, and in winter, shading of 30-50% is appropriate. If the light is too strong, the stems will swell and turn yellow, the leaves will be yellow-green, and growth will slow or stop.

Facility conditions for Dendrobium officinale

Because Dendrobium officinale has relatively high environmental requirements, it needs to be planted in a facility environment. Simple bamboo and wood frame greenhouses and steel frame greenhouses are both acceptable, but good ventilation inside the greenhouse must be ensured, and internal and external shade nets should be installed. If funds are sufficient and Dendrobium officinale is to be cultivated over the long term, building a steel frame greenhouse can be considered, as it has a long service life and a low repair rate. For the plastic film, 12-15 gauge can be chosen according to funds, heat preservation and service life.

1. Ground planting: The soil needed inside the greenhouse should be fully dried in the sun and treated with phoxim for insecticidal treatment to kill the pests and insect eggs remaining in the soil. Inside the greenhouse, use bricks or stones to build seedbeds 15-20 cm high and 1-1.5 m wide, with the length depending on the terrain, spread a 5-10 cm thick layer of crushed stone and other materials with good water permeability on top, and finally spread a layer about 10-12 cm thick of fermented tree bark or wood shavings, coconut shells, bagasse, decomposed fallen leaves or moss as the growing substrate. A 40-50 cm wide passage should be kept between seedbeds for daily cultivation operations.

2. Bed planting: According to the funding situation, seedbeds about 1.2-1.5 m wide and about 80 cm high made of bamboo or steel frames can be built, with 40-50 cm wide passages between seedbeds for daily cultivation operations. Movable steel seedbeds can also be built, with bed width and height similar to fixed seedbeds, but only one passage needs to be left to increase the utilization rate inside the greenhouse. The bottom layer of the seedbed is spread with a 10-12 cm layer of fermented tree bark, chopped wood, wood shavings, coconut shells, bagasse, decomposed fallen leaves or moss as the growing substrate.

Summary: Bed planting is recommended for Dendrobium officinale, because bed planting has better water permeability than ground planting, has the advantage that waterlogging is unlikely to occur in the seedbed and cause root rot of Dendrobium officinale, reduces ground-dwelling pests such as snails, slugs and cutworms, and is beneficial to the healthy growth of Dendrobium. If long-term cultivation is considered, the choice of growing substrate is very important. Accumulated and fermented tree bark, chopped wood and wood shavings are corrosion-resistant, have better air permeability than moss, sugarcane residue and rotten leaves, and always remain in a semi-decomposed state, making them more suitable for Dendrobium officinale cultivation and a relatively ideal growing substrate.