Mycology Dictionary

A gel set from red algae and mixed with nutrients, poured into plates to grow and inspect fungal cultures. Growers use it to check genetics are clean before moving them to grain.

A single sterile bag holding both grain and substrate, separated until you mix them. You inject your culture, and the bag colonises and fruits with no substrate preparation.

A pressure steriliser that uses pressurised steam, from 121°C upwards, to kill all microorganisms, including their resistant spores. At Spore Supplies, every bag we sell as sterile is autoclaved for 2 hours 30 minutes.

A thin layer of moist, low-nutrient material, usually coco coir, spread over colonised substrate. It holds humidity at the surface and encourages even pinning.

A fast-spreading, wispy grey-white mould that grows across the surface of substrate or casing. It looks finer and fluffier than mycelium, which grows in denser, rope-like strands.

The stage where mycelium grows through grain or substrate until it is fully white. Colonised material is then either used as spawn or put into fruiting conditions.

Any unwanted organism, such as a mould, bacteria, or yeast, competing with your mycelium for the same food. Most contamination starts with a lapse in sterile technique.

A living sample of a fungus, usually mycelium, kept on agar or in liquid to store, clean up, or expand a particular genetic.

Coco coir, vermiculite, and gypsum (CVG), the classic bulk substrate for monotubs. Coir holds water, vermiculite keeps it airy, and gypsum adds calcium.

The point where a substrate holds as much water as it can without free water pooling. A common check is a firm squeeze, which should release only a few drops.

A microporous panel on a grow bag that lets gases pass while keeping contaminants out. It lets mycelium breathe in a sealed bag.

A laminar flow hood blows HEPA-filtered air in a steady stream across your workspace, so airborne contaminants are pushed away from open cultures. It's the standard tool for agar and grain work.

One wave of mushrooms from a block, bag, or tub. After harvesting and a rest, most substrates produce several flushes, each usually smaller than the last.

Replacing stale, carbon dioxide-rich air around fruiting mushrooms with fresh air. Too little FAE gives long, thin stems. Too much dries the surface.

The mushroom itself: the part of the fungus that grows above the substrate to release spores. Everything before it is the mycelium doing the groundwork.

The humidity, fresh air, light, and temperature that tell colonised mycelium to switch from growing to producing mushrooms. The right settings vary by species.

Sterilised grain fully colonised by mycelium, used to inoculate bulk substrate. Rye, wheat, and millet are the most common grains.

Transferring colonised grain spawn into fresh sterile grain bags to multiply it. One bag can seed several more, if your technique is clean.

Calcium sulphate, added to grain and substrate to supply calcium and sulphur. In grain it also stops kernels clumping together.

A single microscopic thread of fungal cells. Hyphae branch and fuse to form mycelium, releasing enzymes that break down the food around them.

A self-healing rubber port on a grow bag or jar lid. You inject culture through it with a sterile needle, without opening the bag.

Introducing a culture, such as liquid culture, spores, or grain spawn, into a sterile medium to start colonisation.

Selecting a clean, vigorous section of growth on agar and moving it to a fresh plate. Repeating this leaves a single, contamination-free culture.

Live mycelium growing in a sterile nutrient broth. It colonises grain faster than spores and carries one consistent genetic.

A fast, high-yield substrate of hardwood sawdust and soy hulls, also sold as Masters Mix. Our Master Mix pellets are 60/40 oak to soy hull.

Amber or yellow droplets that mycelium releases, often under stress or when competing with contamination. They aren't a contaminant themselves, but worth watching.

A storage tub converted into a fruiting chamber with holes for fresh air exchange, used to fruit bulk substrate at home.

The network of hyphae that forms the main body of a fungus. It's the white growth that colonises grain and substrate before any mushrooms appear.

Partnerships between fungal mycelium and plant roots, where the fungus trades water and minerals for sugars from the plant. Many UK woodland fungi live this way.

Heating a substrate enough to reduce competing microbes, but below the point that kills them all. It suits low-nutrient substrates such as straw and CVG. Nutrient-rich ones need full sterilisation.

The first tiny mushroom formations to appear once fruiting conditions are right. Pinning is the moment colonisation turns into a crop.

A substrate block that is already fully colonised. You cut it open, give it fruiting conditions, and harvest. It's the quickest route to fresh mushrooms.

The proportion of grain spawn to bulk substrate, written as a ratio of spawn to substrate. More spawn means faster colonisation and less chance for contamination to get a foothold.

A microscopic reproductive cell released by a fungus. Each spore is genetically unique and, in the right conditions, can germinate into new mycelium.

Spores suspended in sterile water. Because every spore differs, results vary more, and germination is slower than with a liquid culture.

A clear tub with arm holes that keeps air still while you work, so airborne contaminants settle rather than drift onto open cultures. It's a low-cost alternative to a flow hood.

Killing every living organism in a material, including resistant bacterial spores. In mycology, that means pressurised steam, from 121°C upwards, in an autoclave or pressure cooker.

A genetically distinct line within one species, selected for traits such as yield, colour, or temperature tolerance.

The material mushrooms fruit from, such as CVG, Master Mix, straw, or hardwood. Grain feeds the mycelium, and substrate is where the crop grows.

The most common green mould in mushroom growing. It often starts as white patches that look like mycelium, then turns bright green as it spores.