Oyster mushroom on Toilet paper

The Mushroom Roll

August 2023

by Melinda Dunnett and the Afrifungi team


Facts About Fungi

Mushrooms are the ‘fruits’ of fungi. The network of thin, fluffy, white fibres (called mycelium) that you sometimes see on dead wood or under leaves is the ‘body’ or ‘plant’ of a fungus (it’s hard to know what to call it because fungi are so different to other living things). Mushrooms release spores (the ‘seeds’ of a fungus) into the air so that they can travel to a new place and grow into a new fungus.

Fungi are the ultimate recyclers. They break down dead plant material (especially the tough, woody parts that not many other things can eat) so that the nutrients can be used again by other organisms. Without fungi (together with insects, worms and bacteria) dead plants and garbage would pile up all over the place.

Oyster mushrooms are some of the easiest mushrooms to grow for food. There are several types of oyster mushroom, for example: grey, pink, gold and blue. They grow naturally on dead branches and tree trunks all over the world. All they need for the mycelium (‘body’) to grow is food (called the substrate - usually some kind of woody plant material like a log, wood chips, sawdust, straw, cardboard, paper or even toilet paper! Surprised that mushrooms can grow on toilet paper? Remember that paper is made from wood! To get the mycelium to fruit (make mushrooms) you need to add lots of fresh air and a little bit of light.

What you need

  • Toilet paper rolls (the more untreated the better)
  • Bowl or plate
  • Clean water
  • Plastic bags or cling film
  • Oyster mushroom grain spawn
  • Spray bottle
  • Permanent marker

How To Do It

  1. Wash your hands well

  2. Place a roll of toilet paper in a bowl or plate. Pour hot water onto it until all parts are wet. Turn it over. If you see dry spots, pour more water onto them

  3. Remove the cardboard tube from the middle of the toilet roll. This should be easy – if it doesn’t want to come out, add a bit more water

  4. Carefully pick up the wet toilet roll (a pair of tongs works well) and put it into a plastic bag (ideally a mushroom grow bag, but any clean plastic bag will do), or onto a sheet of cling film

  5. Before you open your packet of grain spawn, break it up with your hands until it is in small enough pieces to pour

  6. Pour some grain spawn into the middle of the toilet roll. Don’t worry if you spill some into the bag/on the cling film

  7. Close the bag with a rubber band (or tie the top closed) or wrap the toilet roll entirely with cling film. This prevents the it from drying out while it colonises.

  8. Poke some small holes all over the plastic to allow the mushroom to breathe

  9. Place it in a warm place, out of direct sunlight, until the whole roll looks white a fluffy (fully colonised with mushroom mycelium - usually takes 10-14 days, longer in cold weather)
  10. Once it is fully colonised, open the top of the bag or make some larger holes in the cling film. Spray the inside of the plastic (not directly onto the toilet roll) with water once or twice a day and wait for it to fruit (usually takes 1-2 weeks). Place your mushroom roll in a spot that has plenty of fresh air and that gets a little bit of light (enough to read by) but not in direct sunlight - preferably somewhere that you will remember to spray it.  


For our oysters to grow nicely, we need to keep mould and other contaminants like bacteria away from them as much as possible. Mould is everywhere: in the soil, in the air and on your hands. It likes to grow in warm, damp places and will compete with the oyster mushrooms for food and space. Try to work in a clean space, preferably indoors where there is less wind to bring mould spores, wash your hands well, or wear gloves if you have them, and try to touch the toilet roll, grain spawn and inside of the bag as little as possible.

Mushrooms fruit best when they have lots of fresh air and a little bit of light. A mushrooms job is to release spores (‘seeds’) into the air so that they can travel to a new place and grow a new fungus. The mushroom will grow towards air and light so that it has the best chance of sending its spores far and wide

Mushrooms need lots of water (humidity) to grow properly. If your toilet roll dries out it will not grow or fruit. If it is too wet, mould is likely to grow, best is to moisten it lightly a few times a day

Mushrooms should be picked before they release their spores. This happens when the mushroom has fully opened and the outside edges of the cap begin to curl upwards.



Trouble shooting

The mycelium is not growing

This is most likely because the toilet roll was not wet enough, or it dried out during the growing process. Make sure that the toilet roll is damp all over. Make sure that the bag is properly closed. It could also be that it is too wet – the substrate should be damp but not dripping wet – or too hot or cold (25-30C is ideal). Light is not important at this point. Mycelium does not need light to grow, but it also does not need to be in the dark. Just don’t put it in direct sunlight as this will dry it out and make it too hot. Sometimes it just needs more time.

My toilet roll is covered in white mycelium but it’s not fruiting

Once you open the bag to start fruiting, it is very important to keep the toilet roll damp all the time. Mist it with a spray bottle a few times per day. If it dries out you may see tiny mushrooms start to grow and then stop. Make sure it has a little bit of light (enough light to read a book, not direct sunlight) and plenty of fresh air. Fruiting happens better in slightly cooler temperatures (10-14C is ideal) – move it to a cool, damp place. Sometimes it just needs a little more time.

My toilet roll has colours other than white on it
If you see black or blue-green spots it is probably mould. If it is a small spot the oysters may still be OK and may still fruit. If most of your toilet roll goes blue or black then throw it away and try again.

My mushrooms are a funny shape
Mushrooms do not grow properly if they do not have enough air or light. If the CO2 levels are too high they get long, furry stems and small caps – they are trying to reach up high for more oxygen. If there is not enough light they will be long, thin and pale


 How to eat Oyster mushrooms:

You can eat the whole stem and cap, but cut off the bottom end of the stalk if there is still substrate attached. It is best to cook them rather than eat them raw. Fry them in a little bit of oil or butter until they are crispy. Add them to pizzas, pasta sauce, chicken and rice, stir frys or soups.

Recipe for Crumbed Oyster Mushrooms:

  • Oyster mushrooms

  • Little bit of flour

  • 1 egg

  • 1/4C milk (optional)

  • Dry breadcrumbs

  • Oil

Mix 1 egg with 1/4C milk. Sprinkle some flour over your mushrooms. Shake off the extra flour. Dip them into the egg and milk. Coat them with dry breadcrumbs – press them on firmly. Put them into the fridge for 20min. Put some oil into a frying pan and wait until it is hot. Drop the mushrooms into the oil and fry until they are golden. Drain on a paper towel.


Some people can be allergic to mushrooms and mushroom spores. Oyster mushrooms release a lot of spores. Try to avoid breathing them in as they are not good for your lungs. Fruit your mushrooms in a well ventilated place and harvest them before they release their spores (as soon as they reach full size and before the caps turn upwards)

If you'd like to do all of this at home you can order your mushroom spawn from us! Here is the link: oyster-spawn
And don't hesitate to get in touch if you have any questions or feel like this should your little ones should be experimenting with mushroom growing at school ;)
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