How To Know When Pink Oyster Mushroom Substrate Is Fully Colonized

You can tell that your pink oyster mushroom substrate is fully colonized by observing a few key signs:

1. Uniform White Mycelium Coverage

Appearance: The most obvious sign of full colonization is that the substrate will be completely covered with a thick, white layer of mycelium. The mycelium will look like a dense, web-like network that spreads across the surface and deep into the substrate.
No Patches: There should be no visible gaps, bare spots, or areas where the substrate is still exposed. The entire substrate should appear as if it has been “taken over” by the white mycelium.

2. Firm Texture

Substrate Consolidation: When you gently press on the substrate (if it's in a bag or container), it should feel firm and solid. As the mycelium grows and consolidates, it binds the substrate together, making it more dense and compact. A fully colonized substrate should hold its shape.

3. No Unwanted Mold or Contamination

Clean Mycelium: Look for any unusual colors such as green, black, or blue, which could indicate mold or contamination. Fully colonized mycelium should remain a clean, bright white. Any discoloration is a sign that the substrate may be contaminated.

4. Mycelium Reaching Edges of the Container

Growth to Boundaries: The mycelium should reach all the way to the edges of the container or growing bag. In transparent containers, you should be able to see the white mycelium against the walls. In opaque containers, check the surface or lift it to check underneath for uniform coverage.

5. Smell

Earthy, Fungal Odor: A fully colonized substrate will have a pleasant, earthy mushroom smell. If there are any sour, musty, or foul odors, it could indicate contamination, and the mycelium may not be fully healthy.

6. Time Frame

Time Required: For pink oyster mushrooms, full colonization usually takes 10-14 days, depending on conditions like temperature, moisture, and substrate quality. If it's been much longer, and the substrate is not fully white, something may have gone wrong, such as contamination or poor growing conditions.

7. Pinning (Sometimes)

Tiny Mushroom Formation: In some cases, you might see small "pins" or primordia—tiny mushroom growths—forming on the surface, indicating that the mycelium is fully established and ready to fruit. However, pinning can sometimes occur before the substrate is fully colonized, so it's not always a definite sign.

In Summary:

The entire substrate should be covered with thick, white mycelium.
The substrate will feel firm and consolidated.
There should be no discoloration or bad smells.
Time frame: usually around 2 weeks.

Once these signs are present, your substrate is ready for the next step, which typically involves changing conditions to trigger fruiting, such as increasing humidity, lowering temperatures, or exposing it to fresh air and light.