How to coax a second harvest out of your ShroomBag.
One flush is a freebie. A second flush is where you start to understand the mycelium. The block isn't spent after the first wave of mushrooms — it's just thirsty and a little tired. Give it back what it lost and it will fruit again, usually within two to three weeks.
1 — Rehydrate the block (the cold-water soak)
After your first harvest, the substrate has lost a significant chunk of its moisture. The fastest way to get it back is a cold-water soak. Slip the bag (still sealed at the top) into a clean bucket or a deep sink, weigh it down with a plate so it stays submerged, and fill with cold tap water. Twelve hours is the floor, twenty-four is the ceiling. Use cold water — warm water invites bacteria and stresses the mycelium. After the soak, drain completely. Tip the bag, let it run, and squeeze the bag gently from the outside to push trapped water out. A waterlogged block rots; a rehydrated block fruits.
2 — Reset the fruiting surface
If the original cut has scarred over with old mushroom stubs or aborted pins, peel that material away with clean hands or a sterilized blade. You want fresh, white mycelium meeting fresh air. Some growers cut a new X on the opposite face of the bag and leave the original cut to scab over — both approaches work. Put the bag back inside its box (the box is your humidity tent) and resume misting twice a day. Aim the spray at the inside of the box, not directly at the block.
3 — Wait, watch, and read the signs
Pins usually break within ten to fourteen days of the soak. Sometimes faster. If you see condensation building inside the box but nothing pinning, you're too wet — crack the box flaps for an hour to let it breathe. If the surface looks dry and chalky, you're too dry — mist more often. Healthy second flushes are smaller than firsts, often by 30 to 50 percent. That's normal. The mycelium has eaten through most of its easy carbon and is working harder for less.
4 — Know when to stop and plant out
Most ShroomBags give two strong indoor flushes. A few will give three. Once flushes drop below a useful yield, or the block develops green or black mold (Trichoderma, Aspergillus), the indoor run is done. Don't compost it. Don't trash it. Bury the block in shaded mulch outside — under a hardwood log, in a leaf-litter corner of the garden, or in a hugelkultur bed. Mycelium that's failing inside a plastic bag often thrives once it's connected to soil. This is the part of cultivation almost no kit company will tell you about, because they want you to buy another bag. We'd rather you grow mushrooms forever.
A grow kit is a starter culture, not a disposable. Treat it that way and one $25 bag becomes a year of mushrooms.
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