Shiitake Mushroom Grain Spawn - UK


The Shiitake mushroom produces meaty fruitbodies which are highly prized for their amazing umami flavour

This 3782 Shiitake strain is aggressive and can been grown on pasteurised straw substrate as well as sterilised wood-based substrates.

It has an 8-12 week incubation period and is more challenging to grow than other mushroom varieties like Oysters, however the challenge of learning to grow them is well worth it.

This spawn pack includes:

  • 2.8kg of quality Shiitake mushroom grain spawn
  • 20 x Mushroom cultivation bags (can hold 1.5-2 kg substrate per bag)

Difficulty: Medium - Advanced

Shiitake is best suited to growers who have a bit of experience. The mycelium is slower growing and the incubation phase is much longer than most varieties, taking 8-12 weeks.

A 'popcorning' and 'browning' process needs to take place before the fruitbodies develop.

Check out our guide on How To Grow Shiitake Mushrooms for more info.


  • pasteurised straw
  • straw pellets or hardwood fuel pellets
  • sterilised supplemented sawdust

Growing Parameters:

  • Incubation: 20 - 24C, 12 - 15 days + 45 - 60 days ripening phase
  • Fruiting: 12 - 18C, 90 - 95% R.H, <1000ppm CO2
  • Harvest: 4 - 7 days after pinning, 2 crops with 10 days between each flush

    Who Is This For?

    This is for anyone who wants to get involved a step further than our super simple GroCycle Kits.

    With this spawn pack, you can do the whole process yourself, inoculating a bulk load (around 30-40kg) of pasteurised straw or sterilised supplemented sawdust.

    There are no instructions; you'll need to already know how to grow mushrooms.

    If you don't know how to grow mushrooms and you want to learn, then either:

    A good place to start is with our Ultimate Guide On How To Grow Mushrooms

     Important Information

     Note: The spawn contained in this pack is alive and should be used within 1 week of receiving, or can be stored in the fridge for up to 1 month.

    • Free 2-3 day delivery (UK Only)