Spawn Carriers

Amycel mushroom spawn is produced on three substrates: millet grain, Exxpress and Onyxx. Exxpress and Onyxx are Amycel’s high-performance spawns, and are carefully formulated for faster colonization and protection from Trichoderma Green Mold. Our premium casing spawn, PAC, is also available.

Not all products are available for all strains. Please contact you sales representative to find out availability.


Millet grain is inoculated with pure mushroom culture and incubated under carefully controlled conditions. Grain is the traditional carrier for mushroom mycelia, and is used throughout the world. The small size of millet grain is ideal to ensure complete colonization in the compost. 

Exxpress- High Performance Spawn

Amycel’s innovative synthetic spawn substrate provides growers with an alternative to traditional grain spawn. Exxpress typically runs faster than grain ensuring a complete spawn run in any compost. Faster spawn runs, and Exxpress’ proprietary mix of ingredients, helps protect your crop against green mold.

Onyxx – High Performing Spawn

Onyxx is a hybrid substrate that combines the benefits of synthetic and grain spawns.  It also runs faster in the compost and protect the crop again Trichoderma Green Mold.


Casing spawn needs to be consistent and perform under a variety of conditions and soil moistures. Amycel’s premium casing spawn, a mixture of high quality compost and nutrients, performs consistently under the toughest conditions.