What Is the External Nutrition Bag Method for Commercial Morel Mushroom Farming?
The External Nutrition Bag (ENB) method is a commercial morel (Morchella) cultivation technique in which nutrient-filled bags are placed in or beside the mushroom bed after the main substrate has been spawned. Instead of enriching the entire substrate, growers add a controlled external food source that supports the mycelial network and reduces the risk of making the main bed too rich or prone to contamination.
The method was invented in Sichuan, China, in 2000, and it is closely associated with the Sichuan Morel Research Institute, which operates demonstration and manufacturing bases in Anxian and Luojiang. Sichuan is widely regarded as the birthplace of commercial artificial morel cultivation, and the ENB method has become one of the practical techniques used by growers scaling beyond trial plots.
In practice, the ENB approach separates the main substrate from the nutrition supply. The main substrate is prepared and sterilized, then inoculated with morel spawn; later, filled nutrition bags are introduced at set intervals. The bags deliver supplementary nutrients to the colonized mycelium, which helps maintain vigorous growth through the later stages of the crop without overloading the original substrate.
For commercial farms, making nutrition bags by hand quickly becomes a bottleneck. The Sichuan Morel Research Institute offers a fourth-generation ENB Automatic Nutrient Bagging Machine that fills 30–50 bags per minute, or roughly 1,800–3,000 bags per hour. It handles bag weights from 300 g to 1,000 g, runs on 220 V/50 Hz with a 1.5 kW motor, and weighs about 380 kg.
The labor impact is significant: one ENB bagging machine can replace 15–25 workers on repetitive filling and sealing work. This is especially useful during the narrow windows of morel cultivation, when nutrition bags need to be prepared consistently and at volume. More uniform bag weight and fill also help standardize nutrient delivery across a field or indoor cabin.
• Prepare the main substrate with an industrial mixer and bring it to 60–65% moisture before loading the autoclave.
• Sterilize the substrate in a high-pressure autoclave, then inoculate beds with morel mycelium spawn; a practical reference is about 1 tube per 667 m² (1 mu).
• Place filled ENB nutrition bags at regular intervals after the mycelium has established, and keep the crop under UV shade netting and micro-fogging or IoT climate control for stable temperature and humidity. For indoor cabins, this means maintaining roughly 4–28 °C and 70–98% relative humidity with remote IoT monitoring.
Sichuan Morel Research Institute Co., Ltd. supports ENB-based projects with equipment, training, and turnkey farm design for operations from 1 to 50 hectares or more. More details on the ENB bagging machine, substrate lines, autoclaves, and online masterclasses are available at www.cn-localfoods.com.