Common Mushroom Terminology

Updated: Sep 10



The Sporeshift list of commonly-used Mushroom-growing words & lingo.


There's a fair bit of mycology-specific (mycology is the study of fungi) terminology that can get confusing to the uninitiated. Here's our ever-evolving list of mushroom-grower's frequently-used-terms with accompanying descriptions. Hopefully, if you aren't sure of the meaning of a commonly used mushroom-cultivation related word, it will help you out!


Aborting: This happens usually when young mushrooms dry-out, get damaged or get too cold. The mushroom pr pin set will stop growing, dry, yellow in colour and shrivel up.

Agar: A powder derived from sea weed. When dissolved into hot water and allowed to set it has a firm jelly like texture. Selected nutrients are then added, everything is sterilised then poured into petri dishes to do sterile culture work in the laboratory.

Block: Substrate, usually sawdust, held together by mycelium is called a 'fruiting block.'

Cap: The top of the mushroom with gills underneath.

Casing Layer: A layer of water-holding-material, such as compost or coco coir, layered on top of a substrate to promote mushroom growth.

CO2: Carbon Dioxide gas is exhaled by mushrooms. Much the same as humans, mushrooms breath in oxygen (O2) and exhale CO2. CO2 needs to be removed from the growing environment to produce normal size caps, elevated CO2 levels will cause some mushrooms, especially oyster mushrooms, to grow long stems with small caps.

Coco Coir: Soil like medium that holds water, a common casing material or substrate for dung-loving mushrooms.

Cold Shock: Placing a mushroom block into a cold environment - usually for 12 hours - to drop temperature; mimicking a seasonal change to encourage mushroom fruit-body development.

Colonise: When the mycelium is growing from one substrate to the next. Once the intended substrate is completely dense with white, it is fully-colonised and ready to produce fruit bodies or be transferred onto the next substrate.

Contaminant: Something other than white mycelium growing on the spawn or substrate, an undesired mould or bacteria, most commonly trichoderma, a green-coloured mould. Sometimes referred to as "contam".

Culture: A pure mushroom strain that is selected for desirable traits such as nice fruit body formation, size and/or colour. Usually stored and grown on nutrient agar in the laboratory.

Flush: When mushroom blocks produce mushrooms this is called a flush, once harvested there will be a dormancy period followed by the next flush of mushrooms.

Fruit-body, Fruiting Body, Mushroom: The edible part of the mushroom that people are most commonly aware of, this is what we usually see in nature. Essentially, the 'flower' of the organism. Fruit bodies are actually made up of condensed mycelium.

Gills: The underside of the cap, thin lines, almost blade-like where spores drop from: fragile if touched and bruise easily on some species.

Green mould: Trichoderma, the most common contaminant when growing mushrooms, shows up as a light to dark green colour. Very fast growing and will often out compete mycelium.

Gypsum: Fine gypsum is used to enhance mushroom metabolism, adds nutrients and helps material loosen/ break up

Hydrogen peroxide - H2O2: A great surface cleaner used at 3-5% strength, does not need to be rinsed off preparation or mixing surfaces/ containers before mixing substrate. This is a major advantage over bleach.