Mushroom growing bags (50 pack)
Heavy-duty, heat-resistant polythene bags for oyster mushroom substrate. A pack of 50, made to take hot pasteurised material without tearing.
KES 1,500 per pack of 50
The bag is not where the money goes, but it decides whether the batch survives pasteurisation. A bag that splits in the drum, or one that splits later on the shelf, costs you the whole batch, not just the bag.
Ours come in a pack of 50. Message us on WhatsApp with the drum you are filling and the space you have on the shelf, and we will tell you the thickness in microns and the filled size that fit, and whether to stand them on a rack or flat.
Why thickness matters
A grower will fill a bag with substrate that has just come out of hot water or steam, sometimes above 70C. Thin general-purpose polythene goes soft and splits at those temperatures. A mushroom growing bag is made with a thicker, higher-density film for exactly this step, which is why it survives pasteurisation and still seals tightly afterwards.
The other thing a good bag does is hold shape. A bag that folds flat puts air in the substrate, and air gaps are where contamination starts. A bag that keeps its shape keeps the substrate compressed and dense, which is what you want for even colonisation.
How to use them
- Fill the bags loosely but fully, pressing out the large air pockets as you go.
- Tie the neck tightly. A loose neck lets air in and dries the substrate out.
- Punch a small number of holes, 4 to 6 per bag, low on the bag. These let CO2 out while keeping moisture in, which is the balance a mushroom bag needs.
- Pasteurise as usual, then let the bags cool completely before you spawn them.
- Once spawned and colonised, cut a single clean slit where the mushrooms should come out, rather than tearing the bag open.
Sizing it against the rest of your setup
Bag size has to match two other things: the amount of substrate you mix per bag, and the shelf or the fruiting space they will stand in. Rather than guess at the figures here, send us those two measurements on WhatsApp and we will tell you which bag to order..
Common mistakes
- Reusing bags. Do not. Spores and mycelium left on the inside of a used bag will start a crop you did not plan, usually somewhere worse than where you wanted it.
- Punching too many or too large holes. Every hole is a place for the bag to dry out and for contamination to enter. Small and few.
- Thin bags for hot pasteurisation. This is the failure that costs the most.
- Bags too large for the shelf. A bag that is squeezed or leaning is a bag with crushed substrate at one end.
Common questions
What size are the mushroom growing bags?
Message us on WhatsApp with the drum you are filling and the shelf you are standing them on, and we will tell you the thickness in microns and the filled size that fit. It is a two-minute question, and it is how you avoid buying bags that do not suit your setup.
How many holes should I punch in a mushroom bag?
4 to 6 small holes, low on the bag. They let CO2 out while keeping moisture in. More or larger holes dry the substrate out and let contamination in.
Can I reuse growing bags?
No. Spores and mycelium left inside will start an unwanted crop. Once the bag has finished fruiting, open it outdoors so the remaining substrate keeps producing instead of infesting your growing room.
Are these bags suitable for pasteurisation?
Yes, they are made for hot material. Fill, tie the neck and pasteurise as usual, then let them cool completely before adding spawn.
Do I need these bags if I buy a growing kit?
No. A ready-to-grow kit arrives in its own bag. You need growing bags when you are mixing your own substrate and spawn.