7/29/2019 Mushrooms - Grow Them at Home

1/3

Mushrooms: Grow them at Home

The cultivated mushroom,Agaricus bisporus (also calledA. campestris orA. brunnens) may be

easily grow at home with the proper equiptment and care.

Mushroom growing is considerably different from growing plants because it does not require

sunlight. Any dark corner or unused shelter where temperatures are cool and ventilation is

adequate will serve for growing mushrooms. Because a mild, even temperature is essential, thebest times for growing them are spring and fall. The compost preparation should begin about

five weeks ahead of the desired "spawning" time. The proper equipment needed to grow

mushrooms includes: trays, a pitchfork, a watering can, manure, straw, gypsum, a thermometer,

spawn, a pump mist sprayer, a sieve, and peat or sterile soil.

The trays are used to grow the mushrooms in, and must be 10-to-12 inches deep. Trays 2 feet

long by 3 feet wide are commonly used, but trays of other lengths and widths may be used. Theycan be made from scrap lumber and should be held together with screws, rather than nails, for

durability. Ventilation, beneficial for mushroom growth, is provided by placing the trays on

pieces of 2-by-4 lumber or bricks. Trays that stack should be constructed allowing 24-to-30inches between tiers for adequate air circulation. Trays may be placed in the cellar, in a shed,

under a table, in a cool room, or even under a bed. By placing trays in different locations, the

spread of insects and diseases will be limited to only parts of the crop. Whereever the trays areplaced, the area should be kept free of rats and mice and the windows screened to keep out

insects.

To prepare the compost, have available the pitchfork, watering can, straw, manure, gypsum, andthermometer. About a half-ton of com post will fill 60 square feet of trays and yield from 100-

to-150 pounds of mushrooms. When smaller amounts are composted, the pile should be covered

with wet burlap and the burlap watered to keep the pile from drying out.

The most important part of the compost is the manure. The "hotter" (more rich in nitrogen) it is

the better. Horse manure is the best, but chicken, turkey, rabbit, sheep, goat, or even elephantmanures may be used. Cow manure is very low in nitrogen and therefore undesirable. Use fresh

manure, since then it will be the hottest. Thoroughly saturate the manure with water, if

necessary, just to the point of run-off. Add an equal volume of straw that has soaked up waterfor a day. Check with local farmers and zoos for manure and straw. They may be glad to supplyyou with ample amounts! Do not use veterinarian stable manure or any manure that may have

medicines in it since these may be detrimental to the mushroom spawn.

As you mix the manure and straw together with a pitchfork, sprinkle the pile with gypsum. For a

half-ton of compost, 20 pounds of gypsum is needed. Gypsum (calcium sulfate) is available

107 Nott Terrace, Suite 301

Schenectady, NY 12308Phone: (518) 372-1622; Fax: (518) 372-8703

www.cceschenectady.org

7/29/2019 Mushrooms - Grow Them at Home

2/3

from local building supply companies at a low cost. It gives the compost good consistency,helping avoid a sticky texture.

It is preferable to build the compost pile on a cement floor and under cover to discourage insectsfrom entering and laying eggs in it. Once the compost pile is made (and covered with wet burlap

if it is small and apt to dry out), it is left to rest. A stick thermometer or dairy thermometer maybe used to judge when the pile should be turned. When the temperature reaches 160 to 170F.carmelization has taken place. Turn the pile literally inside out, adding water in places where it

is dry and/or white. A thermometer is not essential; the compost may simply be turned once per

week for five weeks, keeping it always moist. One week after the final turn it is time to add the

spawn.

The preferred spawn is dry, flake spawn; dry, brick spawn may also be used. Dry spawn is a

pure culture of the mushroom mycelium in a dormant state. The mycelium is the body of thefungus -- its "roots, stems, and leaves" -- that grows throughout the compost and gives rise to the

mushrooms -- the "flowers" of the fungus. If dry, flake spawn is used; it is mixed into the

compost at a rate of about 1 quart per 15 square feet of growing surface area.

Pile the spawned compost into the wooden trays in heaps. It will be easiest to fill the trays where

they are to stay because once filled they are heavy and difficult to move. After 24 hours, press

the piles flat into the trays using a brick or a piece of wood. Leave a space of about 2 inches tothe top of the tray. If dry, brick spawn is used, pile the compost into the trays and place pieces of

the brick (between the size of a walnut and an egg) into the compost about 1-to-2 inches deep,

spacing them 6 inches apart. Cover the pieces of spawn and press the compost down flat aspreviously described.

In 2-to-3 weeks the compost should become covered with the fine white webs of mycelium. If

possible, the temperature should be increased to about 65 to 70F during these first weeks. In

addition, it will be important during these first weeks to keep the compost moist by water mistingit twice a day. The compost should not be watered by sprinkling or pouring water onto it. This

not only disrupts the delicate mycelium, but may also make the compost too wet for its proper

growth and development.

Once the compost is covered with white mycelium, the casing should be applied and the

temperature may be dropped back to about 55F. A sieve is used to remove any sticks, stones, or

large clumps from the casing material.

The peat or soil should be thoroughly moistened with water, but not soaking wet. The moisture

content of the casing is critical to the development of the mushrooms. Covering the trays withseveral layers of moistened newspaper that are lightly watered twice daily will help maintain the

proper moisture content. In about 10 days the newspaper should be removed and the trays

misted twice daily as before.

A few days later, tiny white pinheads should be visible that will develop into delicious

mushrooms in about a week. The temperature of the area in which the trays are located willdetermine how quickly the mushrooms develop. Cooler temperatures (50 to 55F) will yield a

7/29/2019 Mushrooms - Grow Them at Home

3/3

slower crop over a longer period of time. Higher temperatures (65 to 70F) will yield a fastercrop over a shorter period of time. Both will yield similar amounts. Therefore, it is more

practical to grow the mushrooms at cooler temperatures so as not to be overwhelmed with too

many mushrooms all at once.

Oncethe first mushrooms appear, subsequent oneswill appear in flushes, every 10-to-12 daysfor 3-to-6 months until the compost is exhausted. Between flushes continue to mist twice daily.But do not apply water to developing mushrooms because they most likely will turn brown and

deteriorate.

Pick the mushrooms by grasping over the cap and around the stem and gently twisting. Themushroom will separate from the compost leaving some residual mycelial masses. These should

be removed from the media with a knife to ensure the continued productivity of the tray. The

holes left by the picked mushrooms should be filled with peat or soil to maintain a uniformsurface.

Mushrooms may be picked in the button stage to be eaten raw in salads or with dips. They maybe picked in the typically marketed stage, with the unruptured veil covering the gills under the

cap. These are used in all types of cooking, and store well. The advantage to growing your own

mushrooms is that you may pick mushrooms with opened gills that have fully matured. These

have the best flavor and are useful in sauces or special dishes. Such mature mushrooms do notstore well, and for this reason are never seen in the market.

After the trays cease bearing, the compost is in perfect condition for use as an organicamendment for vegetable or flower gardens or for mulches around trees and shrubs. The trays,

areas where compost is mixed and where mushrooms grow, should be thoroughly scrubbed andair dried. Trays may often need to be replaced because they decay while in use. Cleaning and

removal of all organic debris will help discourage diseases and insects.

Mushroom growing kits of many types are available commercially. When the instructions are

followed, they will produce batches of mushrooms. These kits are best used as gifts,

experiments for children, or an introduction to mushroom growing. However, for the seriousgrower they are impractical; the price per pound of mushrooms produced is often more than

grocery store prices. Mushroom trays with prepared compost are available from some

commercial mushroom growers or from some nurseries. These may be a practical means of

producing mushrooms for those who are unable to prepare the compost media themselves.

Prepared by: Cornell Cooperative Extension, Albany CountySlightly Revised: 6/03