About your Oyster mushroom kit

Tips for good production- Drain the straw well- squeeze out excess moisture when it is upside down

The better you shake your spawn around, the quicker it will fruit.

1) Where should I put my kit once I have prepared it?


8-24 degrees C. The warmer it is, the quicker to first fruiting, cold temperatures, below 10 degrees, will slow things up, but it will still fruit.

In summer, high temperatures can delay fruiting. If possible avoid setting up 3-4 weeks before peak temperatures are expected to be above 24 degrees.

AVOID  wind, direct sun, air conditioners, heaters because they will suck moisture from the bag.


Dim to bright.

AVOID direct sun.


 All of the following have been used successfully sink, shower, bath, table top, carport, garage, shade house, greenhouse, caravan, tent, spare room

AVOID  Fruit bowls, rubbish bins/areas, compost, wet mulch


a) If there are fruit flies/vinegar flies/fungus gnats in your environment, keep the protective cloth on until mushrooms form, then carefully remove it. Squash the odd small fly you see in the bag- the mushroom will digest them.

Sorting the problem- Move the growing bag to another area and spray a short burst of fly spray (pyrethrum) into the white bag then seal it for 12 hours with an elastic band. Open the bag and bring the sides down and up a few times to flush the air out. Spray another short burst and seal for 12 hours. Repeat once more and all insects should be dead.

IMPORTANT NOTE- Do this before fruiting or between flushes.

b) If the bottom of the bag seems wet and hasn't turned white after 3-4 weeks- cut an extra 2-3 crosses in this area to help it evaporate moisture- squeeze any obvious moisture out and refresh the newspaper with dry newspaper. Dampen only after 3-4 days. Leave this part out of the white bag- It is a good idea to keep the white cloth over the top during this period.

2) How long until fruiting?

Fruiting can begin as quickly as 2 weeks after starting, in summer, to 4+ weeks in cold areas in winter. This is normal as all mushrooms grow slower in cold weather. You can speed them up by bringing them into a warmer environment but make sure they are not exposed to dry air from air conditioning, heaters, wind or direct sun.

Things to try-

a) If the newspaper in the bottom dries out, sprinkle or spray water on it. This will need to be done more frequently during frosty weather and in areas near dehumidifiers or air-conditioners.

b) If you notice the spawn (white growing area) seems clumped after 10-14 days, give the bag a careful shake to spread it out

3) There are mushrooms forming behind the plastic.

 Sometimes mushrooms are so keen to grow they miss the air holes. It can happen if the bag isn't tight against the straw.

Things to try Release them by cutting a 'V' shaped flap that sits over them and opens as they grow.

4) Is anything happening?

Yes! Even though it appears as though nothing is going on the fine threads will be doing their work.

Checking for good things!

a) The seed grains developed a white fluff that spread into the straw.

b) The straw looks a lighter colour than after it was soaked.

c) The straw developed an aniseed smell after 4-12 days.

d) Smell is mildly damp.

e) The straw looks like white mould.

5) How will I know it is about to fruit?

If you are keeping the cloth on, the first thing you will notice are bumps against the fabric where the crosses are- time to take the cloth off and lower the bag 3/4 of the way down.

If you have the cloth off, the white colour will suddenly intensify and the threads will thicken. White pinhead sized bubbles will form at the slits. These will soon thicken, develop a dark colour and grow a stalk.

6) When to pick?

Caps start off dark coloured and expand to 2-30cm across. They will not grow much bigger once the edge of the cap has flattened out. This is when the dust-like white spores drop from the gills- some people are allergic to them. Do not leave mushrooms on the kit after this stage if they are indoors.

Young mushrooms (edge of cap still curled under) Crisp and succulent. Subtle flavour.

SUITS Soups, salads, omelettes, pizza.

Mature mushrooms (edge of cap not curled or facing upwards and cap is wavy like a clam shell) Stronger flavour. Easily ripped into strips.

SUITS Stir fry, patties, fritters, battered, crumbed, barbecued.

7) My mushrooms started to grow, then dried up and turned yellow/brown.

This is because of dry air sucking moisture out of the caps. Check the white bag was up before starting to fruit and that the newspaper was moist. Make sure there is no direct sun or heat/air conditioning nearby. If the air is dry (frosty, or less than 60% humidity, spray the inside of the white bag a few times a day. They're still good to eat!  Pick and add soy sauce,  wine or water to re-hydrate them during cooking. Note that the mushrooms in that flush will not start growing again if you water them after they have dried.

8) I think my kit is not going to fruit

Contact us we'd like to help.

.9) What straw can I use?

Wheat, barley, oat or rye straw are the best. Straw should be a light yellow, dry and free of mould or rot. Pea straw is not a true straw and whilst it may work for a while it encourages weed fungi and contamination.

Where to get more straw? - pet shops, horse/stock food suppliers, strawberry growers


"I keep my mushroom kit in the shower and after the second flush I showered with the kit and got a great third crop, looking forward to my fourth."

"I got two flushes and then I gave up and thought it wasn't going to give me any more so I threw it in the garage in disgust. One day my husband came in and said have you seen how many mushrooms are in the garage? The bag was covered!"

" We took the plastic bag right off after 3 weeks and placed the straw on a plate.  We water the top of the straw  every day with warm water. We tip off the excess water and it fruits really well."

Since receiving my spawn from you guys I've been having a great time growing oysters on all sorts of stuff, I get a lot of spent coffee from work and it seems to keep me in good supply. A.S. Auckland



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Site opened August 1999                                                             Last updated Jan 2011