How to Plant Mushrooms

Planting mushrooms may seem mysterious, but it's an incredibly rewarding project for any gardener or food lover. Unlike traditional vegetables, mushrooms grow from spores rather than seeds and require very specific growing conditions. With the right setup and a bit of patience, you can grow fresh mushrooms at home, either indoors or outdoors. Whether you use a ready-made kit or start from scratch, the key lies in creating the perfect environment for them to thrive.

Understanding Mushroom Spores and Mycelium

Unlike plants, mushrooms reproduce through spores that eventually grow into a root-like structure called mycelium. This mycelium spreads through organic matter and forms the base from which mushrooms sprout. Mycelium can be bought as spawn, which is essentially a pre-grown network of fungal threads ready to colonise a suitable substrate. Choosing good quality spawn is crucial, and different mushrooms require different types of organic matter to grow in.

Choosing the Right Type of Mushroom to Grow

Before planting, decide which type of mushroom suits your space and conditions. Button mushrooms and oyster mushrooms are among the easiest to grow, especially for beginners. Shiitake mushrooms are another popular variety, but they typically require hardwood logs. Each variety has its own requirements for moisture, temperature and light, so selecting the right type will increase your chances of success.

Creating the Ideal Growing Environment

Mushrooms need darkness, moisture and warmth to develop properly. A shaded shed, cellar or kitchen cupboard can work well indoors, while shady sheltered areas in the garden can work outdoors. The temperature should be consistent and ideally between 12°C and 24°C depending on the species. Humidity is also essential, and the substrate must be kept moist but not soaked. A simple spray bottle is often used to mist the surface regularly to prevent it from drying out.

How to Prepare the Substrate

The substrate is the material in which your mushrooms will grow, and it must be prepared properly. Different mushrooms grow on different substrates. Straw, sawdust, coffee grounds or composted manure are all common options. The substrate must be pasteurised or sterilised to remove unwanted bacteria or fungi that might compete with the mycelium. Once cooled, the mushroom spawn is mixed into the substrate and packed into a growing container or bag.

Caring for Mushrooms During Growth

Once the spawn has been added to the substrate, the mycelium begins to spread and colonise its environment. This stage can take a couple of weeks, during which time the container should be kept in a dark, warm location with high humidity. As the mycelium matures, small pinheads will begin to appear. These are the beginnings of your mushrooms. Once they start developing, they may need a little indirect light and good airflow to mature properly.

Harvesting Home-Grown Mushrooms

When the mushrooms reach full size and before the caps begin to curl upwards, they are ready to be harvested. Use a gentle twist at the base or a clean knife to cut them free. Picking them at the right time is important for the best flavour and texture. In many cases, a single setup can produce multiple flushes of mushrooms over a few weeks, as long as the mycelium remains healthy and the conditions are maintained.

Common Problems When Planting Mushrooms

Growing mushrooms can sometimes be tricky due to the specific environment they require. Contamination is one of the most common issues and often occurs if the substrate wasn’t sterilised properly. Mould, bacteria or competing fungi can all affect your crop. Mushrooms can also fail to fruit if the temperature or moisture levels are not right. Checking your setup regularly and adjusting humidity or airflow can help solve many of these issues before they ruin a crop.

Outdoor Mushroom Beds and Logs

If you want a longer-term mushroom patch, outdoor beds or logs are worth considering. Hardwood logs can be drilled with holes and filled with spawn, then sealed with wax. Left in a shady part of the garden, these logs can produce mushrooms like shiitake or lion’s mane for years. Straw beds are another option and work well for oyster mushrooms during the warmer months. These methods require more space but less daily attention once established.