Skill level
Blue Oyster Mushroom Grow Block
Sale price
$36.95
Tax included
Beginner
Grow location
Indoors or in a grow tent or chamber
Growing temp
10°C to 21°C
Time to grow
1 to 2 weeks for first flush
Block weight
2.2kg
Shelf life
Use immediately for best results or store refrigerated for up to 2 months.
GROW LIKE A PRO
Grow Blue Oyster Mushrooms at Home
Our Blue Oyster Mushroom Grow Block (Pleurotus ostreatus) is perfect for beginner growers. These cool-climate mushrooms are fast to fruit (just 1–2 weeks) and deliver a generous first flush. Provide them with cool and humid conditions and watch as deep midnight blue pins transform into elegant, steel-grey clusters with a velvety texture and umami flavour.
Grown on our certified organic, Australian-made substrate, Blue Oyster mushrooms are easy to grow, high-yielding and reliable. Whether you're cooking up stir-fries, pastas or just trying your hand at growing something different, our Blue Oyster mushroom grow blocks make home cultivation simple, satisfying, and seriously impressive.
Most Frequently Asked
What is the difference between a Grow Block and a Mushroom Grow Kit?
There are three main differences between our Grow Blocks and our boxed Mushroom Grow Kits - size, packaging and difficulty.
Size
The Grow Blocks are commercial-sized mushroom fruiting blocks. Each weighs 2.2kg. Whereas our Mushroom Grow Kits are benchtop size and weigh just under 1kg. This does mean that you will grow more mushrooms off these bigger grow blocks as long as you provide them with the correct growing conditions. More substrate = more flushes and more mushrooms!
Packaging
The Grow Blocks don't come in a nice giftable box, they just come as they are in their plastic grow bag - nothing fancy! If you're wanting a cute shroomy gift then the boxed Mushroom Grow Kit is the go.
Difficulty
And lastly, we offer some of the more difficult to grow species in these bigger block options. Some of the species on offer won't just grow on your kitchen bench - they are fussier about temperature and humidity. We recommend setting up a shotgun fruiting chamber at a minimum or a grow tent and be sure to choose the right species for your climate if you can't control the temperature!
How many mushrooms will I grow?
Our Big Mushroom Grow Blocks are commercial-sized substrate fruiting blocks. These 2.2kg blocks average between 400g - 600g of mushrooms on the first flush in ideal conditions. Your yields will be affected by the conditions in which they're grown so be sure to pay close attention to the growing conditions listed on each block page and any instructions provided with your shipment to avoid disappointment.
There are slight variations between mushroom species, for example Snow White Oysters are heavier than Gold Oysters but you can expect a decent first flush from these big blocks!
As the blocks are quite hefty, they will produce more crops - or flushes as we call them in the mushroom industry - you can expect 2-3 but if you're a gun grower you can get 4, 5...depends on how patient and persistent you are. The first flush will always be the biggest and fastest to grow. Subsequent flushes may take several weeks in between.
Hot tip 🔥 after a couple of flushes move your spent blocks to a full-shade area of your garden and keep them moist. This spent block 'graveyard' will explode with mushrooms when the temperature is right or you get a big rain event.
What are the best grow blocks for beginners?
If you've never grown a mushroom before we recommend you start off with one of our smaller mushroom grow kits - these come in the easiest to grow mushroom types like Pink Oyster and Warm White Oyster.
But if you're ready to go BIG then we recommend starting off with an Oyster mushroom or the Lion's Mane grow block.
Be sure to use the filter options to select the best mushroom species to grow in your climate if you can't control your growing conditions. We've also categorised them into Beginner, Intermediate and Advanced difficulty.
If you're having trouble with your grow block be sure to reach out to our expert growing team - we've got years of experience as commercial mushroom farmers and can give you all the tips for growing amazing mushrooms using our big grow blocks (they're exactly the same grow blocks we use in the biz 😜).
Do I need any additional equipment to use grow blocks?
To get the most out of your big grow blocks we recommend setting up a Shotgun Fruiting Chamber at a minimum. You can watch our step-by-step tutorial video below.
Most of the species on offer as big grow blocks require temperatures between 18°C - 21°C to grow, and constant humidity above 85%. This can be hard to achieve without a little gear such as a grow tent or humidifier.
If you don't have a home-growing set up such as a chamber or tent then it is crucial to choose a grow block with a growing temperature range which matches your current weather and you may need to be manually misting your block a lot to keep that humidity high!
Should I take the blocks out of the plastic bag?
Leave the block inside the plastic grow bag for the duration of your grow. The plastic stops the substrate from drying out and protects it from outside air which may spread contamination onto the surface of the substrate after some time.
The only exception to this is if you're growing Shiitake. The Shiitake grow block should be removed from the bag entirely as Shiitake like to fruit from all surfaces of the block and need air movement around the block to help with mushroom formation.
Can I store the grow blocks to use later?
If you receive your grow blocks and you're not ready to grow them straight away you MUST store them in the fridge! If not, they may spoil or grow inside the plastic, preventing you from getting a good harvest.
If you see that your block is starting to form mushrooms under the plastic while in the fridge you will need to grow it. Our big grow blocks contain mushroom species which can grow at cold temperatures so long-term cold storage may not prevent them from growing but it can slow them down.
What substrate are the grow blocks made from?
Little Acre's Mushroom Grow Blocks are Australian made and Certified Organic.
The substrate is processed and inoculated at our Brisbane facility.
The substrate consists of hardwood sawdust and a special blend of certified organic nutrients including wheat and soy products.
What growing conditions do I need to provide?
You need to provide the correct temperture and humidity to trigger your mushroom grow blocks to fruit mushrooms.
For most species available in mushroom grow blocks the ideal temperature is 18°C and 90% humidity.
If your block is not growing, it is most likely the correct conditions have not been met and you may have to adjust the position of your block or provide cooling or extra humidity.
Please check the recommended growing conditions listed on the product pages for each type of block before you make your purchase. We are not able to accept returns or exchanges on grow blocks if you purchase the wrong species for your current conditions.
Where is the best place in my house to grow mushrooms?
In nature, mushrooms grow in the cool, moist areas of the forest where they are sheltered from the weather and wind, so it's best to find a place like this in or around your house.
Many people say to grow your mushrooms in the bathroom as it's an area that often has humidity from showers. While this can be good, airflow is also important and small enclosed spaces can cause your mushrooms to suffer from a lack of oxygen.
Keep your grow blocks out of direct sunlight and don't put them in a greenhouse unless it's fully shaded.
Keep it out of wind or away from heaters which can cause it to dry out. Air conditioning can also dry out your mushrooms so you may need to mist your block more regularly if it's going to sit in an air conditioned room and it's not protected by a chamber or grow tent.
It's also a good idea not to set up your mushroom growing area next to potted plants, household bins, compost bins, or soil as these can harbour other fungi, moulds and insects such as fungus gnats which can spread mould to your mushroom blocks.
The best place to grow mushrooms is in an enclosed space where you can control the temperature, humidity and air circulation. This is often why serious home-growers choose to build a mushroom grow tent.
If you are sensitive to mushroom spores or have respitory illness keep any mushroom growing set ups out of your house or enclosed areas that you frequent. We recommend wearing a respirator mask for protection when working inside your grow tent if you're growing more than a couple of blocks frequently.
Are grow blocks harder to grow than mushroom grow kits?
Yes. The species of mushrooms available in our big grow blocks are more difficult to grow than the smaller mushroom grow kits simply because they have narrower growing temperature ranges.
But if you provide the conditions listed on the blocks and can maintain those conditions during the growth cycle then you should have no trouble growing amazing gourmet varieties at home!
We recommend setting up a shotgun fruiting chamber at a minimum or a grow tent and be sure to choose the right species for your climate if you can't control the temperature!
Do you offer grow block subscriptions?
Yes! If you're looking for a regular supply of grow blocks to keep your fridge well stocked with gourmet mushrooms why not check out our Grow Block Bundle! Mix and match and change your selection monthy to try lots of different types of mushrooms. Monthly subscribers receive great value with a subscription discount.
