Home / Mushroom Cultivation / Additives & Chemicals / Calcium Nitrate (100g)

Oxidiser

1 / 2

Additives & Chemicals

Calcium Nitrate (100g)

A soluble 15.5-0-0 calcium nitrate: a calcium and nitrogen supplement for compost-grown mushrooms like button and portobello, and for the casing layer that goes on top.

£5.00

Sold for cultivation and lab use. Keep away from heat and combustible material.

Soluble salt
Dissolves fully in water, no residue left in the mix

Dual mineral
Supplies both calcium and nitrate nitrogen

Handle with care
An oxidiser and an irritant, keep off skin and away from heat

Grade15.5-0-0

Nitrogen15.5% (mostly nitrate, a little ammonium)

Calciumabout 19%

FormDry, free-flowing granules, fully water-soluble

Best forCompost-grown mushrooms (Agaricus) and casing

Not forGrain spawn or sterilised bulk substrate

What it is

A soluble calcium and nitrogen feed

This is standard 15.5-0-0 calcium nitrate: 15.5% nitrogen, mostly fast-acting nitrate, plus about 19% calcium. It is a dry, free-flowing granular product that dissolves fully in water and is supplied ready to use.

How to use it in mushroom growing

For compost-grown mushrooms and casing

Its place is with the compost-loving mushrooms grown on composted substrate, the Agaricus group: button, cremini and portobello. It is not part of the grain or sterile-substrate side of the hobby.

Into the compost

When you build and wet a mushroom compost, calcium nitrate adds soluble nitrogen to feed the composting and calcium to firm up the structure. Dissolve it in the water you are adding, or scatter and mix it through evenly so it is not left in pockets.

Into the casing

A small amount worked into the casing layer adds calcium, which supports firm, even pinning. Gypsum or chalk are the usual casing calcium sources; calcium nitrate also brings a little nitrogen with it.

Go light

It is concentrated, so use a modest amount and adjust to your recipe. Dissolve it fresh rather than storing made-up solution.

Where not to use it

Not for grain or sterile bulk

Do not add it to grain spawn or to sterilised bulk substrate such as sawdust, coir or straw bags. Soluble nitrate sitting on a sterile, nutritious medium feeds bacteria and mould before your mycelium can use it, which invites contamination. On those, calcium comes from gypsum and any extra nitrogen from bran-type supplements, not from a soluble salt.

Storage

Keep it sealed and dry

It is hygroscopic, so it draws moisture from the air and will clump if left open. Store it sealed in a dry place, away from children and pets.

Sources

Sold for legal gourmet mushroom cultivation and laboratory use. An oxidiser and irritant: handle and store with care and keep away from children.