How to grow your own Shiitake Mushrooms

Shiitake mushrooms (Lentinula edodes) are a common edible mushroom native to East Asia. In the wild, they grow in clusters on decaying deciduous hardwood trees/logs/stumps.

Shiitakes have been used for millennia both as a staple ingredient in Asian cuisine and in traditional Chinese medicine. Shiitake are now cultivated worldwide, making up about 25% of the total production of mushrooms globally.

Growing shiitake mushrooms can easily be done in a household hobby-setting and even commercially to trade. We offer everything you need to grow your own shiitake mushrooms at home, or in the garden in NZ: from >> shiitake spawn, to >> inoculated dowels for making your own shiitake garden logs, through to >> ready-made Shiitake sawdust block grow kits (that are ready to fruit!)

Benefits of consuming shiitake - Shiitake mushrooms can help boost the immune system, fight cancers and support healthy heart function by lowering cholesterol levels. Shiitake are low in calories, high in fibre and offer a generous amount of B vitamins (they are one of the few vegetarian sources of vitamin B12). When sun-dried with the gills up, shiitake mushrooms can take up to 10,000 x's the daily dose of vitamin D!

Growing Shiitake Mushrooms on sawdust fruiting blocks

Growing shiitake mushrooms on ready-made blocks is a more short-term option than growing on logs. Some of you will be making your own shiitake blocks from >> spawn, while others may be getting a >> ready-made shiitake block that is ready to 'fruit' or start producing mushrooms as soon as the block is delivered. Ready-made blocks are great as unique gifts, as well as a fantastic science project for the kids!

Growing Shiitake Mushrooms from a ready-made block

When your shiitake block arrives, it will be in a clear plastic bag with a wee filter patch (so it can breathe, yes mushrooms breathe like we do). As soon as possible, you will need to remove the plastic bag and spray the block down with water. The block will be spongey to touch and some of the brown bits may flake off when spraying the block with water. Don't worry, this is totally normal and will encourage healthy mushroom production. Allow the block to drip dry for a few minutes and move to a good spot out of direct sunlight in preparation for mushrooms growing ('fruiting').

Mushroom Development - Water the block for a few days until baby mushrooms begin to appear ('pinning'). As tempting as it may be, DO NOT touch the baby mushrooms while they are forming as they are very fragile at this stage. Mist/spray mushrooms with water daily while they are growing. If you are in a very dry environment, mist the block twice a day to avoid the mushroom caps drying out.

Harvesting - Shiitake mushrooms are ready to harvest as soon as you can see the gills underneath. Harvest by cutting the stem off as close to block as possible. Fresh shiitakes will last in the fridge for up to two weeks.

Successive fruiting - Once you have harvested all the mushrooms off the block initially, leave the block to rest and dry for 2 weeks. To induce the second fruiting, submerge the block completely under cold water for 6-12 hours. Remove the block very carefully from the water and sit to allow it to drain. Block will be soft, heavy and fragile until the water drains back out of it. Once it has drained enough, put back it in your chosen spot for growing.

Making your own Shiitake blocks: The 4-stage life-cycle of the Shiitake fruiting block

A shiitake block that has just colonised

❖ Stage 1 "Colonising"- You have mixed your shiitake spawn with sterile substrate, now the block is colonising and held together by white mycelium. The block is made up of sterilised sawdust and bran inside a special >> mushroom filter-patch-bag which allows air exchange while keeping a sterile environment inside the bag. Leave the block in the plastic bag until stage 3 is complete.

Shiitake block in the "Popcorning" stage

❖ Stage 2 "Popcorning"- The block begins to ‘popcorn’ forming bulbous knots, bumps and blisters all over it. Once the 'popcorning' process starts, avoid handling the block as much as possible. The block is now essentially shock-sensitive, as, in nature, shiitake mushrooms will commonly fruit after the tree that they are growing on falls and impacts the ground. Touching, moving, or handling the block during this stage can induce premature fruiting, which will reduce mushroom yield. If the block does begin to produce mushrooms under the plastic the bag will need to be removed and move to "Stage 4 - Fruiting/ Mushroom Production Time"

Shiitake block browning ready for pinning

❖ Stage 3 "Browning"- The surface of the block will begin to go dark brown, many first-time-shiitake-growers think that this is contamination, but it is ideal ... this is what you want to see! It is ready to fruit once the block is at least 50-70% brown. The block is now ready to be handled and produce mushrooms! This is when you remove it from the plastic bag.

Shiitake block pinning baby mushrooms

❖ Stage 4 "Pinning and Fruiting"- Fruiting/ Mushroom Production! Remove the plastic bag by cutting with a clean razor, it is not a problem if you cut the block a little. Spray water directly on the block until dripping wet morning and night for 2-3 days until you start seeing little mushrooms appear. You can stop spraying when the mushrooms begin appearing on the block. Harvest as soon as you see the gills underneath the mushroom cap.

Growing Shiitake Mushrooms on logs in your garden

Abundant shiitake, growing on logs in a Kiwi-garden

An easy, low maintenance way to grow shiitake mushrooms is to use >> dowel spawn to inoculate logs. Mushroom logs are a bit more of a long-term option and can take anywhere for 6 months to a few years to start producing mushrooms depending on the size of the log. Once colonised, the bigger the log, the longer the log will produce mushrooms and can keep producing mushrooms every year for several years!!

Get more guidance on >> growing mushrooms on logs here.

How to store and cook shiitake mushrooms

Once harvested, shiitake mushrooms can last up to 2 weeks in the fridge. They are best stored in a paper bag, as the paper allows them to breathe. If left in a plastic bag or sealed container, they can sweat and will not last quite as long. It is best to keep them in the main part of the fridge rather than the produce drawer for this reason.

Shiitake mushrooms have a very savoury, rich umami flavour. Shiitake are best used fresh, however they can be dried or dehydrated for later use as they maintain their flavour when stored dry. They are used in many classic Asian dishes from stir fries to noodles and ramen. **Important note- Shiitake stems are very tough and essentially inedible, so cut the stem off as close to the cap of the mushroom as possible.

Here is a simple recipe for sautéed shiitake mushrooms- (can be a side dish, an entree or added to dishes mentioned above.. most of the time they don't make it to the intended dish before being snacked on!! )

Sautéed Shiitake Mushrooms

Ingredients

500g fresh shiitake mushrooms

2-3 tbsp soy sauce / tamari

1 tsp Siracha (if you like it spicy)

1 tbsp lime juice

2 tbsp sesame oil

2 dashes toasted sesame oil

1) Cut the the stems off as close to the gill as possible and discard. Slice larger mushrooms in quarters or halves, leave smaller mushrooms whole.

2) Heat sesame oil in a large skillet over medium heat.

3) Add mushrooms and cook about 5 minutes, stirring occasionally until browned.

4) Mix together and add lime juice, siracha, soy sauce, and toasted sesame oil, cook for about 2 minutes until glossy and dark brown.