The color of oyster mushrooms during their "undeveloped" stage (before they grow into normal fruiting bodies, in the primordia → small bud → young mushroom stage) changes as follows, making them very easy to identify:
Primordia Stage (Just emerging as small white dots):
When they first emerge from the mycelium, they are pure white to milky white small protrusions, like tiny pearls or grains of rice, very clean and cute.
Needle-head Mushroom/Small Bud Stage (1-5mm):
Still pure white to snow-white, the cap hasn't opened yet, like tiny white nails stuck to the substrate. This stage is the most beautiful, and many growers take photos of its "snow-white" appearance.
Coral Stage/Young Mushroom Stage (Cap begins to differentiate, but hasn't flattened yet):
Cap tip: Light gray → bluish-gray → grayish-brown (gradually showing color from the center)
Cap edge: Still white to grayish-white
Overall, it looks "gray in the center, white on all sides," resembling small corals or seashells; this is the so-called "coral stage."
Young oyster mushrooms that are almost ready for harvest (cap diameter 3-6cm, not yet fully flat) will have caps that turn a uniform dark gray, grayish-brown to a bluish-gray hue, with the edges still curled. This stage has the most even and beautiful color, and many people choose to harvest and sell these "young mushrooms" at this time for a better price.
A simple way to remember the color sequence (before they are ready for harvest):
Pure white dots → Snow-white small mushroom buds → Gray center with white edges (coral-like) → Overall dark gray/grayish-brown
In short: Truly "undeveloped" oyster mushrooms always start as pure white, gradually turning gray from the center. They will never have yellow, brown, or green variegated colors.
If yellow spots, brown spots, or green dots appear in the young mushroom stage → 99% of the time there's a problem; it's not that they haven't developed, it's that they're diseased!
Hopefully, this time we finally got a healthy color – white → gray → dark gray. This is the normal growth process of oyster mushrooms!
