Fungi Farm Mushroom Windowsill Kit - King Oyster

Growing Instructions:
This kit is designed for indoor growing. Choose a clean area away from direct heat sources and draughts. Avoid direct sunlight to prevent overheating. Mushrooms prefer indirect, filtered light.
Please note: Any white bubbly growths indicate where mushrooms are forming, and will later grow into king oyster mushrooms.

Step 1. Activate the substrate
• If you see tiny bubbles on the top of the pack, completely remove the plastic bag from the package.
• Soak the substrate block in water for about 30 minutes.
• Place the block back into the container and cover with the transparent lid. This allows better oxygen intake and triggers mushroom development.
Tip: Wash your hands well before touching the substrate block to prevent cross contamination with any other fungi.

Step 2. Create the right environment
• Store the kit in a sheltered, humid area at 16-19°C (61-66°F).
• Avoid direct sunlight to prevent overheating. Mushrooms prefer indirect, filtered light
• Spray lightly twice a day so the outside remains moist.
• This stage mimics autumn conditions, which king oyster mushrooms prefer.
• Make sure the transparent lid remains seated on the container. This helps retain moisture while allowing enough fresh air inside.

Step 3. Encourage mushroom formation
• After around one week, more bubble-like growths will appear and start developing into mushrooms.
• Continue spraying regularly during this stage.

Step 4. Harvest
• Harvest when the smallest mushroom cap reaches 2 to 4 cm in diameter and the cap has just curled down.
• Grasp a bunch by the cap and break them off carefully.

Step 5. Further harvests
• After the first harvest, which is usually the largest, continue spraying.
• A second crop normally appears after around 2 weeks.
Please note: The yield in subsequent crops will decrease as nutrients are used up.

For more information and guidance check out our Gardening Guides.

Harvesting: Take a mushroom between your fingertips and carefully pull it out with a twist of the hand. Do not pull out without twisting and do not harvest undersized mushrooms. Always water regularly to prevent the ‘cover compost’ from drying out.

Seeds and garden supplies will normally be delivered within the time period stated against each product as detailed above. Plants, bulbs, corms, tubers, shrubs, trees, potatoes, etc. are delivered at the appropriate time for planting or potting on. Delivery times will be stated on the product page above, or in your order acknowledgement page and email.

Orders for packets of seed incur a delivery charge of £2.99.

Orders which include any other products will incur a delivery charge of £6.99.

Where an order includes both packets of seeds and other products, a maximum delivery charge of £7.99 will apply - regardless of the number of items ordered.

Large Non-standard items may incur a higher, lorry delivery charge. Charges will be calculated at checkout, but an example of the lorry charges are listed below.

• Red - £9.99.
• Purple - £2.99.

For more information please visit our delivery charges information page by clicking here.

For more information on how we send your plants please visit our Helpful Guide on plant sizes.