How To Grow Oyster Mushrooms

Growing Oyster mushrooms is a fun and fascinating experience. There are few things like watching your spiderweb of mycelium grow day by day as you eagerly anticipate the production of delicious mushrooms. Thankfully for us, with little patience and a big appetite, it only takes 1-4 weeks for your first flush of mushrooms to make their way to the dinner table (depending on your method of growing).  

Oyster mushrooms are great for novice growers, as they are some of the hardiest and most vigorous species you can cultivate. For many people, Oyster Mushrooms open a gateway to the greater world of mushroom cultivation. Contrary to what some people believe, you do not need a laboratory or special equipment to grow mushrooms. It can be done at home, often with nothing more than the materials you already have at hand. 

In this guide, we’ll give you the basic run-down of everything you need to know to grow these delicious morsels at home.

Primary Materials

Whilst your method of mushroom growing will dictate what is required to grow mushrooms with, the below are the most commonly required. 

• Spawn: This is the “seed” you will use to “plant” your mushroom. It is typically composed of grains colonized by the fungal mycelium of your choice. This is the only specialty item you will need for the cultivation process, as it cannot be found in stores. This being said, you can purchase it online or from a local laboratory in your area.  Make sure to buy spawn for a variety suitable for the season and climate.
  
  
• Note: While spawn can be made at home, it is a rather technical and not recommended for beginner growers.
  
  
• Substrate: Substrate is the primary material that your mushrooms will grow and feed on. While many different substrates are used in     cultivation, we recommend straw or hardwood fuel pellets for beginners.
  
  
• Growbag or  Container: Mushroom grow bags are designed for mushroom cultivation and incorporate a built-in filter. They are great and not too expensive but must be specially ordered.
  
  
• Alternatively, you can use a clean plastic bag with a 3-4 cm cut or a 20-liter bucket with eight evenly spaced 1 cm holes. These openings should be covered with micropore tape to prevent insects, bacteria, and other fungi from entering. You can also recycle 1-liter containers, plastic water jugs, or anything you imagine. Just make sure it is thoroughly cleaned and disinfected before use. 
  
  
• Isopropyl Alcohol: This will be used to disinfect hands, spawn bags, tables and on other materials used during the inoculation process.
  
  
• Beeswax: This is used to seal the "wounds" created whilst using an outdoor log mushroom growing method.
  
  
• Mushroom Growing Kits - The easiest one stop solution, these kits contain everything you need to begin growing oyster mushrooms at home. Current varieties we offer are Pink and Yellow Oyster and King Oyster Mushroom Kits.

Step-by-step Guide - The Spawn and Substrate Method.

1. Prepare Your Substrate

For first-time growers, using either fuel pellets or straw is recommended. Fuel pellets are probably the easiest of the two, but they can be more expensive. Fuel pellets require no additional preparation, while straw should be cut into 10-20 cm pieces (you can use a machete and a wood block or a weed-whacker for faster prep). While not always necessary, it is recommended to rinse your straw before pasteurization.

2. Pasteurizing Your Substrate

Pasteurization is a process that kills any harmful microorganisms from your substrate. It is a fundamental process to ensure your substrate can be easily colonized by your mushroom of choice without competing with other organisms. 
    

• Fuel pellets can be easily pasteurized by simply rehydrating them with boiling water. Use 1 litre boiling water per 1 kg of pellets.
  
  
• Straw can be steamed for one hour or submerged under boiling water. One easy method is to place your straw into a mesh vegetable sack and then place this into a 20-liter bucket. Put freshly boiled water into the bucket until the straw is fully submerged. Soak for 1-2 hours. Alternatively, you can soak the straw for 12 hours in water treated with lime at 1.5 grams/litre. Use what is known as “hydrated lime” and not your typical agricultural lime. After soaking, hang your sack of straw for 3-4 hours until it is fully drained and no longer dripping.

3. Inoculate The Substrate

Inoculation is the act of introducing a fungal culture into a new growth medium. For the context of this article, it refers to mixing your mushroom spawn with the pasteurized substrate. Before doing any inoculation, it is recommended to first thoroughly wash and disinfect your hands, working table, plus any of the materials you are using.

To begin, simply start placing alternating layers of spawn and substrate in your grow bag/container. For beginners, using about 15% spawn (15g of spawn for every 85g of hydrated substrate) is recommended, but you can go as low as 10%. Avoid touching the spawn directly with your hands. Instead, simply break it up in the bag it comes in and pour it onto the substrate. 

Once inoculated, be sure to seal your container properly. It’s recommended to seal the lids with an extra layer of plastic wrap for buckets or plastic containers.

4. Incubation

Now, simply place your grow kit in a dark space with adequate ventilation. A closet, guest room, or under your bed is good enough. It doesn’t have to be complete darkness. Most strains like temperatures between 15-20 Celsius, although some varieties prefer temperatures outside of this range. Your spawn producer should provide this information. Incubation typically takes 2-4 weeks.

5. Fruiting

Mushrooms require high levels of ambient moisture to grow properly. If you live in a naturally moist climate, fruiting is much easier. In dry climates, you may have to find a microclimate and supplement it with irrigation or misting. Some nice microclimates can be in a heavily shady part of your yard, under your patio, or even in your bathroom. Watering around your grow kit can help raise ambient moisture levels.

If you do not see mushrooms appearing after 3-4 weeks, increasing airflow and moisture is recommended. Do this by removing filter patches or making a 2-3 cm slice in your grow kit. Spray this area regularly to encourage mushroom growth. Small mushrooms called “primordia” should pop up after a couple of days and only take between 3-6 days to be fully mature and ready to harvest. After your first harvest, getting 2-3 more flushes from your grow kit is possible.

Step-by-step Guide - The Outdoor Mushroom Growing Log Method.

1. Prepare Your Log

Your log should be 15-20cm in diameter and around 1 meter in length.

• Hardwood is best (oak, beech, birch, alder, ash, elm etc).
• Fruit trees (apple, plum, cherry etc) are also good but will take longer to fruit.
• Soft wood / pines / conifers cannot be used due to their natural anti-fungal properties.

We recommend the logs should be used between 2-8 weeks after cutting from a living tree.

2. Purchase your spawn dowels

You should aim to obtain approximately 30 pre inoculated mushroom spawn dowels / plugs. We sell Outdoor log inoculation mushroom growing kits, so if you are wondering where to buy mushroom log growing kits, look no further than Merryhill Mushrooms or these can be found on eBay etc. The Current Oyster Mushroom Variety spawn we offer is White Oyster, a delicious and meaty mushroom.

3. Setting Up Your Mushroom Growing Log

You should take an 8mm drill bit if using standard size wooden dowels, (ours are standard) and create rows of holes, typically 5/6 per log, of setting these evenly across the log, rather than in one continuous flat line. 

Place your spawn plugs within these holes you have created, hammering them in flush with the surface off the log, then seal these off with melted wax. You should expect 12-18 months for the colonisation process to occur.

You will find another blog post on this subject and process here 

Step-by-step Guide - The Indoor Mushroom Growing Kit Method.

1. Ascertain which variety of Oyster Mushroom youd like to grow.

Each kit and variety of mushrooms you grow will enjoy different temperature ranges and conditions to be followed in order to bring fruiting bodies. Our Pink and Yellow Oyster Mushroom Growing Kits require a growing location temperature of under 21'c whilst our King Oyster Mushroom Growing Kits require under 20'c

2. Setup Your Grow Kit

Follow the instructions relevant to your kit, setting up to the requirements, as we have touched on a few different oyster kits we sell as mushroom growing kits, please follow the links below to take you to dedicated mushroom growing guides relevant to each mushroom specie.

How To Grow Yellow Oyster Mushrooms

How To Grow Pink Oyster Mushrooms 

King Oyster Mushroom Growing Guide

Conclusion

Due to the vigorous and adaptable nature of Oyster Mushrooms, they make a great first step into the world of cultivation. Once you’ve mastered this, you can begin to explore the world of other gourmet mushrooms, such as Lion's Mane, Shiitake, Reishi, and Enoki. These can sometimes be more delicate, but you can cultivate them at home using a very similar process.

Mushroom Growing is growing in popularity and you will be able to grow many mushrooms at home with these methods.

Have fun and happy growing!