A Step-by-Step Guide to Growing Shiitake Mushrooms

A Step-by-Step Guide to Growing Shiitake Mushrooms
Growing shiitakes at home is easy and fun! It can add variety
to both your garden and dinner plate. Shiitakes are especially
useful for cooking with, as they have four times the flavour of
white button mushrooms.
In addition to their fine flavour, shiitakes also offer
medicinal and health benefits. Shiitakes have extremely high
levels of protein, potassium, B vitamins, calcium, magnesium
and phosphorus, as well as all essential amino acids. Even
more, shiitakes have antiviral and immunity-boosting
properties and can be used to fight viruses, lower cholesterol,
and regulate blood pressure.
A Step-by-Step Guide to Growing Shiitake Mushrooms
With a small investment and a little work, shiitake mushrooms can easily be grown on hardwood logs
right in your own backyard. Nearly a year before the mushrooms grow, a log is inoculated with
mushroom spawn by drilling several holes into a log, filling the holes with mushroom spawn, and sealing
them. For the next 8-12 months, the log is left to sit in a moist, shady area. In the spring, the log is
emerged in water for 2 days to “shock” the fungus into fruiting. Anywhere from 4 to 14 days later, the
mushrooms will begin to appear, and shortly thereafter can be harvested.
Step One
Cut hardwood logs
Month February to March
Materials/Tools Needed
Saw (chainsaw) and appropriate safety equipment
Standing (live) hardwood trees 5 to 7 inches in diameter, 2 to 4 feet in length (Oak, maple, birth,
poplar, beech, hornbeam, ash, etc.)
Or contact information for someone willing
to thin a few trees
The first step in growing shiitakes is gathering
the medium in which they will be grown.
Traditionally, shiitakes are grown in oak logs.
Shiittake means oak mushroom (shii = oak,
take=mushroom). We have found that shiitake
will also grow well in many hardwoods.
In New Brunswick beech trees are plagued with
a bark disease called nectria or beech canker.
Shiitake seem to love these gnarly logs.
Cut beech logs
Shiitake logs need to be cut live just as the sap starts to run in late February or March and allowed to die
sufficiently before inoculation. Any of the tree’s natural fungus-fighting attributes remaining in the log will
effectively reject the shiitake spawn.
Logs should be cut into manageable sizes to be manipulated during it’s new life as host to shiitake
Step Two
Obtain Shiitake Spawn
When - April to May
Materials/Tools Needed
Contact information for mushroom spawn supplier (David Boyle of
Maritime Microbiological, Truro, N.S.)
- or Richterts Herbs www.richters.com/ in Ontario
The second step to growing shiitakes is obtaining mushroom spawn.
Mushroom spawn is the reproductive structure of the mushroom. Some
microbiologists and mycologists (fungispecialists) sell mushroom spawn in
breathable bags filled with sawdust.
Place your order at least 6 weeks in advance of the
time you would like to inoculate your logs, giving it enough time to grow.
Once you obtain spawn, keep it refrigerated and sealed in the bag until ready
for use. (Or follow the instructions provided for spawn in plugs).
Step Three
Inoculate Logs and Prepare for Storage
Materials/Tools Needed:
Hardwood logs from Step One
Spawn from Step Two
Drill (not cordless)
Wood drill bit that is slightly bigger
than the inoculator tool
Extension cord for drill
Wax mixture (2 parts beeswax: 1 part paraffin
approximately 1/8 cup is enough for 20-30 holes
Tin can to melt wax
Hot plate to heat wax can
Metal spoon
Bleach solution (1 part bleach: 10 parts water)
Inoculator tool or funnel with dowel plunger
Rags for spills (clean rags not used for grease)
Mushroom spawn
When - May
Funnel with plunger or inoculator tool - either
can be used for inoculation
To inoculate the logs, you will need to arrange a
workspace that is as clean as possible to reduce the
chances of contamination by bacteria, and out of the sun to prevent damage to the spawn. It is
also recommended that the drill bits and inoculator tool be disinfected by rinsing them in a mixture
of bleach and water.
There are five steps involved in inoculating the logs:
Start by melting the prepared mixture of beeswax and paraffin in a clean tin can (rinse the can with
your bleach solution first) on a hot plate. When cool, the wax mixture needs to be soft, but not too
soft that you can put a fingerprint in it. Conversely, the wax cannot be too brittle that it cracks and
falls off before the initial log-soaking period. When heated, the wax mixture should be liquid.
2. Drilling holes into log
While the wax is melting, start drilling the
inoculation holes in your logs. Using a drill
and drill bit, drill holes evenly into the log
about 3 cm deep, and 20 cm apart along the
length of the log. The holes should be
closer together (about 10 cm apart) around
the diameter of log. The mushroom
mycelium grows through the wood more
quickly along the vertical length than around
the diameter. For each 1 meter-long log,
there should be about 20 to 30 holes.
3. Pushing spawn into log using inoculator
tool or funnel with plunger
Take the inoculator tool and push the open
end into your bag of spawn, filling the spout.
Place the inoculator over the hole and push
down on the plunger on the top, forcing the
spawn into the hole. The spawn should be
pushed into the hole enough so it is just slightly
lower than the bark.
4. Covering holes with wax mixture
Cover the spawn-filled holes with hot, melted
wax by spreading a small amount over the
spawn-filled holes with a clean metal spoon.
Wait until the wax has cooled enough to stay
in place before turning or moving the log.
The wax is used to kill off any bacteria and to
protect the spawn from insect and weather
damage once outside.
5. Shiitake logs stacked, growing mycelium
Once you are finished inoculating the log, lay it
on the ground horizontally. If you have more
than one log, stack the logs in opposing
directions horizontally. Make sure to put the log
in a moist, shady environment, such as under a
tree to protect it from the sun and wind. Think of
where you find mushrooms growing in the wild
and try to find or create a similar environment for
your shiitake logs.
For the following 12 months, the log(s) should rest undisturbed. In these months, the mushroom spawn
will spread mycelium throughout the log. You will know your log has rested long enough when you are
able to see the mycelium on the ends of the logs the following spring. It will usually appear white and
fuzzy, like mould, but it may brown from exposure to the air.
Step Four
Soak the Logs
When - the following May or June
Materials/Tools Needed:
Tub or pond large enough to submerge logs (i.e. bathtub, kiddie pool)
Stopper to plug tub while soaking logs
Clean water for soaking logs
Weights (rocks, other logs, etc.)
Hoses to fill tub
Stand/area to rest logs in vertical position after
Spray bottle or hose with spray nozzle
In order to encourage the shiitakes to fruit in the
following spring, the mushroom must be “shocked”.
This is done by soaking the log(s) in water for 2 days.
Place the log(s) in a barrel or tub filled with water.
Make sure the log(s) are completely submerged.
Alternatively, you may soak the log(s) in a pond or
lake, provided the water is relatively clean. You will
probably need weights to keep the logs under water,
as they tend to float.
Step Five
Place Logs on Racks
Logs soaking
When - Throughout the Growing Season
After being soaked, remove the log(s) from the water, and place them in an upright or vertical position by
propping them up against a tree, where it is moist and shady. During this fruiting stage, the log must
remain moist and may require misting or watering if weather
is hot
and dry.
Shiitake Logs Racked Vertically
Shiitake Logs Racked Horizontally
With Mushrooms Growing
Step Six
Harvest Mushrooms
Month—Throughout the Growing Season
Materials/Tools Needed:
Bowl & Knife
After 4 to 14 days after soaking, the shiitakes will begin to
appear on the log(s). They are ready to be harvested when
they reach full size, approximately 5-8 cms in diameter.
Take a knife and cut the mushroom stem closest to the
bark. The mushrooms can be eaten raw, cooked, or
dehydrated for later use.
If conditions are right, it may be possible to harvest the
mushrooms a second or even third time in the same
Mushrooms ready to be harvested
Repeat steps four and five in July or August when the first batch of shiitakes have stopped
During harvest time, you may encounter the shiitake mushroom’s
only pest—slugs. There are a number of non-toxic control
methods for slugs. Planting perennials, such as delphiniums,
foxgloves, and primroses, near your log will naturally repel slugs.
The slugs can also be trapped by placing cabbage leaves and
wet newspaper, or cups filled with stale beer, spoiled yoghurt, or
a mixture of
Slugs: Shiitake’s number one
Step Six
yeast and water near the log that the slugs will congregate in.
These can then easily be taken away. If you only have a few
logs, it will be easy enough to
remove the slugs by hand.
Winter Storage
When - Late September/Early October
In the fall, after the mushrooms have stopped growing, it is time to allow the log to rest again.
Lay the log down horizontally on the ground in its previous moist and shady spot. Repeat steps 4, 5,
and 6 every year. Your shiitake log should produce mushrooms for another 4-5 years.
Additional Shiitake Mushroom Information
Shiitake Recipes
Lost Creek Shiitake Mushroom Farm
Oakshire Mushroom Farm
The Mushroom Information Centre
Slug Controls
Earth Easy
Pioneer Thinking
North Coast Gardening
Growing and Harvesting Shiitake Mushrooms
Agriculture and Agri-Food Canada
Grow your Own Mushrooms
Ohio State University
Ontario Woodlot Association