Mushroom grow kits
Mushroom grow kits, ready to fruit.
Flush Blocks are ready-to-fruit mushroom grow kits for gourmet varieties like lion’s mane, oyster and shiitake. Each one arrives sealed, already colonised and ready to open. They grow best in a Flush cabinet, and you can grow them without one with a bit more care.
Choose a variety
Every Flush Block we sell, with its current price and availability.
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What is in a Flush Block
A Flush Block, sealed and ready to open. Nothing to mix, sterilise or prepare — the block has already done the slow part before it reaches you.
Each block comes in a kraft box with a perforated panel on top. Tear the panel away and cut a small X in the bag underneath with a clean knife or scissors wiped with alcohol, to avoid contamination. That is where your mushrooms grow.
Two ways to grow
Grow it in Flush, or on its own
In a Flush cabinet Open the block, place it in the cabinet and close the door, then either choose a preset or set your own targets. Flush holds the temperature, humidity and airflow from there, so there is no misting schedule to keep. All you need to do is keep the water reservoir topped up — a full reservoir lasts at least a week.
Without a cabinet You can, but it is harder. Outside a controlled environment you are managing humidity and fresh air yourself, and results vary a lot with the room and the season. Our guide to growing mushrooms at home in Australia covers how, and grow tent vs fruiting chamber vs Flush compares the setups.
Varieties
Popular grow kits
Lion's mane grow kit
A shaggy white mushroom with a tender, pull-apart texture and a mild, seafood-like flavour. From a ready-to-fruit block it takes about 14–21 days to harvest, and it is rated a beginner variety. See the Lion's Mane Flush Block and our guide to growing lion's mane at home.
Oyster mushroom grow kits
The quickest to fruit: most oyster varieties are ready about a week after you cut the bag open, and king oyster takes a little longer. Choose from snow white, blue, golden, phoenix, pink, warm white and king oyster. Pink, golden and warm white oyster cope best with a warm room. Our guides cover growing oyster mushrooms at home and king oyster.
Shiitake grow kit
Deep umami flavour and a meaty bite, ready in about 7–10 days. Shiitake is the one variety we sell that should come right out of its packaging, because it likes to fruit all over the block. See the Shiitake Flush Block and our guide to growing shiitake at home.
Australia-wide
Delivery
Flush Blocks are posted with Australia Post.
Postage is worked out from your postcode and shown at checkout before you pay.
Up to 6 blocks travel in one parcel.
Blocks ship separately from the Flush Cabinet, so they go in their own order.
Buy one at a time, or subscribe so the next block turns up when you are ready for your next grow.
Can I grow a Flush Block without a Flush cabinet?
You can, but it is harder. Outside a controlled environment you are managing humidity and fresh air yourself, and results vary a lot with the room and the season. Our guide to growing mushrooms at home explains how.
Do I need any experience?
No. The block arrives already colonised and the cabinet manages the conditions, so there is no substrate to prepare and no daily routine to keep up.
How long until I can harvest?
Most oyster varieties are ready about a week after you cut the bag open, and lion's mane in about 14–21 days. Each product page lists its own time to harvest.
How many harvests will I get?
Most blocks fruit more than once. The first flush is usually the largest, with smaller ones after it, and the block is finished when it stops producing.
How are grow kits delivered?
Flush Blocks are posted with Australia Post, up to 6 to a parcel. Postage is worked out from your postcode at checkout.