Organic Grey Oyster Mushroom Culture Block

Easily harvest your own fresh mushrooms with our ready-to-grow fruiting blocks.

• Variety: Grey Oyster, Pleurotus ostreatus.
• Yield: between 1.5 and 2 kg (approx. 3.3–4.4 lb) of fresh mushrooms over 3 harvests.
• Composition: wood sawdust, cereals (including alfalfa), oyster mushroom mycelium, lime. Net weight: approx. 4.8 kg (about 10.6 lb).
• Dimensions: 25 x 20 x 20 cm (about 10 x 8 x 8 in) (L x W x H)
• Origin: Belgium (Mycosphere)

Note: yield figures are estimates based on our production experience but are not guaranteed. Productivity depends on growing conditions and the grower's experience.

Our quality commitment

We produce our mycelium under laboratory conditions, ensuring varietal purity and optimal quality.

We produce our mycelium in a 100% organic way, and all our products are certified "BE-BIO-01, Agriculture Belgium" by CERTISYS.

📦 Using the fruiting block

If you can't use the block right away, keep it in the refrigerator for about 2 weeks. This variety can be grown year-round, with an ideal temperature between 12°C and 20°C (54–68°F).

1. Make a slit on the side of the block at the level of the substrate.
2. Push the air out of the bag thoroughly to keep the mushrooms from growing inside.
3. Lay the bag down with the opening on the side.
4. Keep the bag moist until the pins appear.
5. Maintain a humidity of 80 to 90% while the mushrooms are growing.

Use our minispray or our professional foggers to maintain optimal humidity.

⚙️ Growing parameters

🌱 Where to grow it

Grow indoors (kitchen, garage, cellar). Oyster mushrooms need a little light to grow. Favor indirect sunlight and avoid anything that could dry out the block: drafts, radiators, direct sun. Oyster mushrooms like humidity but don't like being constantly soaked.

🔄 Harvesting

Harvest the clusters before the edges of the caps curl up and start to turn slightly brown. Early in their growth, the caps can double in size each day. When growth slows and the caps turn light gray, it's the right time to harvest. Harvesting the mushrooms young gives better storage life and a more tender texture.

Pull off the clusters by twisting them. Remove any leftover pieces of stem on the substrate and keep it moist until the next harvest.

We usually get 3 harvests per block. The first is the most abundant; each following one is roughly half the size of the previous.

Oyster mushrooms keep for about 7 to 10 days in a paper bag in the refrigerator. For longer storage, you can freeze or can them.

💡 Tips for later harvests

To encourage productivity of the second and third harvests:

• Rehydrate the bags by soaking them overnight in water, then drain them and put them back into cultivation.
• Apply a cold shock by placing the block in a cool spot overnight (refrigerator or outdoors). This mimics the arrival of winter and encourages the mushroom to reproduce.

Legal notice for Belgium: "Organic growing substrate: pasteurized and inoculated mushroom-farm substrate" (Derogation No. EM470.J). Do not consume the substrate.