An Expert’s Guide To Growing Oyster Mushrooms In Buckets

Oyster mushrooms will boost your culinary game. They’re versatile, tasty, and loaded with vitamins, minerals, and antioxidants. They’ll flourish on your kitchen counter or garden with a few simple ingredients – in under four weeks from start to finish. You’ll likely get multiple ‘flushes’ of mushrooms from the same container, too. Introducing “Bucket Tek”!

Why Oyster Mushrooms?

Oysters are among the easiest mushrooms to cultivate at home. They’re hardy, fast-growing, and not picky about their food source or growing conditions. They’ll grow happily on straw inside a bucket with holes in the side – the mushroom clusters will grow out of these when ready.

How Does it Work?

In nature, mushroom spores germinate on something nutritious – like soil, a dead tree, or manure. Throughout the summer, mycelium will spread through that area (usually turning it white). When it’s fully ‘colonized’ in the autumn/fall, mushrooms will grow out of it to spread their spores; this is what we’re replicating with “Bucket Tek”:

1) Introducing mycelium to a warm, wet ‘underground’ space to colonize inside a bucket.

2) Changing to a cooler, humid ‘fruiting’ stage where the mushrooms appear.

Which Oyster to Grow?

Any ‘side-fruiting’ oyster will work using this method. Pink and Yellow oysters grow well in hotter climates, while Grey/Blue Oysters do better in cooler places. Avoid King oysters, as they like to grow on a flat surface.

What Will I Need to Grow Oyster Mushrooms?

Ingredients

• Oyster Mushroom Grain Spawn – This is the equivalent of mushroom ‘seeds’; a quick Google search will find many options. 100g is enough for a 10-litre bucket, but you can use more if you want to.
• Straw  – This is the ‘substrate’ or ‘soil’ from which the mushroom mycelium will eat and grow. Chopped straw is best, although any will do. Pet shops are a good place for this.
• Gypsum (optional) – Also known as calcium sulfate, this adds nutrients for a better harvest.  If you use it, aim for around 5% of the dry weight of the straw you use.
• Boiling water – for pasteurizing straw.

Equipment

• A mixing container – This can be a large cooking pot with lid or a PP5 plastic bucket with lid.
• A large metal spoon
• A container for growing in – A plastic bucket with a lid, a well-washed yogurt pot or any other solid plastic container.
• Drill – This will make the holes the mushrooms will grow out of.
• Medical tape – This breathable tape will cover the holes while the mushrooms are ‘colonizing’ (the ‘underground’ stage of growth).
• A spray bottle – to humidify your mushrooms as they grow.

How to Grow Oyster Mushrooms

Pasteurizing Straw

1. Pour your straw into a clean mixing container.
2. If you are using gypsum, add it to the straw.
3. Add boiling water and mix to cover the straw. Leave the whole thing to cool.
4. Drain the excess water from the container when it’s back at room temperature.

Preparing a Growing Container

1. Drill 12mm holes 4 inches apart around the outside edges of the growing container. A little smaller will work if you don’t have a drill bit that big.
2. Cover each hole with medical tape.
3. Drill several tiny holes in the bottom of the bucket for drainage – leave these open.

 Mixing in the “Seeds” – and the “Underground” Phase

1. Massage your grain spawn through the bag to separate each grain.
2. With clean hands, put a layer of the prepared straw in the bottom of your container.
3. Follow this with a scattering of grain spawn.
4. Make a ‘lasagna’ from layers of pasteurized straw and grain spawn until you have filled the whole container.
5. Put on the lid and leave in a warm, dark, and relatively clean place for two weeks. A good temperature range is 21-24°C (70-70 °F), but each strain will have its favorite colonization temperature, so check you’re meeting its requirements.

The “Overground” Phase – Growing Mushrooms!

1. After two weeks, open the container and ensure the whole surface is white. If so, it is time to put your container into “fruiting” conditions.
2. Remove the medical tape from the holes and move your container into a cooler place in daylight to encourage the mushrooms to grow. This can be inside or outside – out of direct sunlight.
3. Keep the outside of the bucket humid by misting it with a water sprayer a few times a day. If you live in a dry place, you can spray the inside of a plastic bag and put it over the container to create a humidity ‘dome.’ Make sure to remove this regularly to introduce fresh air and extra humidity.
4. After a few days, you will hopefully see baby mushrooms appear in the holes.  Around five days after this, your mushrooms should be ready to harvest!

Harvesting Your Mushrooms – And Getting a Second Flush

1. Your mushrooms are ready when the edge of their caps flatten or turn upwards.
2. To harvest, grab a cluster and gently twist it until it comes away from the container. You can harvest mushrooms when they are ready.
3. When you have harvested your bucket, rehydrate it – soak it in a bigger bucket of water for around four hours – and then return it to fruiting conditions for the next “flush.” You may get many “flushes” of mushrooms from one bucket.

Enjoy!

Always cook before eating. Oysters are excellent in soups and stews or torn into strips and fried. For a more succulent mushroom, broil them in a bit of water until the pan goes dry – and then throw in some oil to crisp them up on the outside.

If you have too many mushrooms to eat right away, you can store them in a plastic tub with the lid open in the fridge. If you want to preserve your harvest, you can dry them in a dehydrator until cracker-dry, then store them in an airtight container for when you want to rehydrate.

A warning for the big growers – if you intend to cultivate lots of oysters, it’s a good idea to ventilate your fruiting space, as Oyster spores can cause aggravation if inhaled. Large-scale growers use some kind of “fruiting chamber” to achieve optimal conditions in a closed environment – and remove spores using an extractor fan.