Fruiting Blocks, Sawdust Spawn, or Outdoor Logs: Which Mushroom-Growing Method is Best?
If you’re new to growing mushrooms, one of the biggest decisions you can make is choosing which mushroom-growing method is best. You’ll have three main options to choose from. In this article, horticulture expert Matt Dursum explains the pros and cons of fruiting blocks, sawdust spawns, and outdoor logs.

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There are dozens of species of easy-to-find edible mushrooms you can grow at home. You’ll save money and trips to the grocery store. You’ll also have more control over what you’re eating.
Growing mushrooms isn’t as difficult as many people would make it seem. All you need are a healthy spawn and substrate. A substrate is the organic material a fungus uses to feed and produce the delicious fruiting bodies we call mushrooms.
Besides other tools such as spray bottles, containers, and thermometers, selecting the right substrate is an important step. Each species has its preferred substrate and growing method. If you get it wrong, you may not have much of a harvest.
If you’re getting into producing your own mushrooms, it’s time to compare the differences between growing methods and their substrates. Continue below to learn more about fruiting blocks, sawdust spawn, and outdoor logs and which mushroom cultivation method is best.
Fruiting Blocks

Fruiting blocks are some of the easiest mushroom-growing methods to use at home. Instead of transferring your spawn to logs or containers, these blocks let you harvest straight from your kitchen or counter.
Regardless of your knowledge and experience, you’ll find these kits easy. A huge variety of edible mushrooms grow with this method. Each block is sold as a growing kit, with easy-to-follow instructions and healthy spawn already in their substrate.
Fruiting blocks are made of sterilized substrate which can contain spent grains, sawdust, and other organic materials. After mixing the substrate, mushroom growers inoculate it with mushroom spawn, which grows mycelium throughout it. When it matures in the right conditions, it sends out its edible fruiting bodies or mushrooms.
Pros
You’ll get to grow some of the most exotic and delicious species from fruiting blocks. Enjoy varieties such as pink oyster mushrooms, lion’s mane, and even shiitake.
They are easy to set up and maintain. Simply follow the instructions and keep them in the right environment.
Another benefit is their diversity. There are a lot of species that flourish in these nutrient-dense blocks. If you want a diverse indoor mushroom collection, these blocks are the way to go.
Finally, you can grow them indoors, any time of the year. From the heat of summer to the depths of winter, as long as your indoor space is suitable, these mushrooms will thrive.
Cons
Fruiting blocks can be more expensive than other methods. They are small, so you’ll have to buy more for a big harvest.
Another con is that fruiting blocks typically only last for a few harvests. After they stop producing mushrooms, you’ll have to reorder new blocks to keep up your harvests.
Sawdust Spawns

Sawdust spawns are another wonderful method to enjoy a bountiful harvest. These spawns are substrates consisting of moist hardwood sawdust. Mushroom growers inoculate the sawdust with mycelium. Once the mycelium is flourishing in the sawdust, move the inoculated sawdust to containers, logs, or outdoor garden beds.
Several species grow well as sawdust spawns. Species such as blue oysters grow vigorously from this substrate. Once your blue oysters are ready, move them to their final location and enjoy bountiful harvests.
Pros
Sawdust spawns are easy to maintain and move. Once the mycelium is growing, you can place them in containers or outdoor spaces.
These methods are also cost-effective. You’ll get a lot of use out of one sawdust spawn. If you grow them correctly, they’ll produce several bountiful harvests.
You’ll enjoy growing fungi with this method for several seasons, depending on where you move them. Sawdust spawns allow you to get creative. Because of their versatility, you can experiment with several growing conditions or even grow multiple species together.
Finally, sawdust spawns are great for getting mushrooms to grow in your lawn. Try species such as wine caps in your outdoor garden bed. Simply combine the sawdust spawns with a suitable substrate, such as wood chips, and enjoy rich and earthy fungal fruits in as little as two months.
Cons
Sawdust spawns are not as user-friendly as fruiting blocks. They take a little extra upkeep for them to thrive.
You’ll have to find a sterilized substrate for the mycelium to grow in. Not all hardwoods or containers work, so you’ll have to be knowledgeable about the species.
These spawns have to stay moist throughout the growing cycle. They dry out quicker than wood spawns or blocks. Once they lose moisture, it’s hard to revive them.
Another thing to be aware of is contamination. Because you’ll grow sawdust spawns outdoors, there’s more chance that they become contaminated by fungi and bacteria living in your yard or garden.
Outdoor Logs

Outdoor logs are one of the most mushroom-growing methods. First, you’ll need to have plenty of hardwood logs and the right spawn.
To use outdoor logs, you’ll need to first drill some holes for your plug spawn. These small wooden plugs have thriving fungal spawns living in them. You’ll insert these plugs into the holes in the logs and they’ll spread throughout the wood.
Once you inoculate the logs with spawn, you’ll enjoy mushrooms for years to come in your outdoor spaces. Some of the most common and beloved species thrive in outdoor logs, including shitakes.
Not all wood types will work. Look at your specific spawn’s instructions to select the right hardwoods. The best hardwoods for most mushrooms include:
- Sugar maples
- Oaks
- American beech trees
- Birch trees
- Ironwoods
- Hop hornbeams
Pros
There are a lot of pros to using outdoor logs for your spawn. One of the main benefits is how easy it is! All you need are a few logs, a drill, and a high-quality plug spawn.
Another benefit is the long-lasting availability of your log-grown mushrooms. Each season, you’ll simply harvest what you please.
Because of the bountiful harvest, you’ll have an abundance of harvests. This saves you plenty of money, especially if you love cooking with mushrooms.
Finally, there are plenty of varieties that thrive on logs. You can grow several species on different log piles, giving you easy-to-harvest varieties.
Cons
Although growing these tasty fungi on logs is easy, there are a few cons to be aware of. First, outdoor cultivation can be quite intensive when it comes to harvesting and inoculating. You’ll have to drill tons of holes manually and when harvest comes, you’ll be busy.
Once the fruiting bodies mature, you’ll have to harvest them quickly. Then, either eat them, store them in the fridge, or dehydrate them. You’ll have a lot of goodies to process, so you may lose a lot of your harvest.
Unlike indoor cultivation, outdoor cultivation is seasonally dependent. You’ll only have a small window to enjoy your your harvest.
Finally, you’ll have to find the right wood species for your spawn. Most species thrive on hardwoods such as oaks and maples.
Other Methods

There are many techniques for producing edible mushrooms globally. Each one has its pros and cons, especially when growing commercially.
Fruiting blocks, sawdust spawn, and outdoor logs are the easiest growing methods for home cultivation. However, there are other popular methods. These are not as easy for growers at home and carry more risks.
Many commercial growers create mushroom compost by mixing organic materials like wheat straw and moisture. The commercial growers inoculate the substrate with mycelium. The mycelium creates huge harvests of edible mushrooms to supply grocery stores and produce markets.
Foraging is another popular and ancient method for harvesting edible fruiting bodies. Mushroom foraging is growing in popularity, however, it’s difficult, time-time-consuming, and often foragers are left with nothing. It also carries significant dangers and even the risk of death if you misidentify your targets.
Key Takeaways
Growing these delicious fungi at home is as simple as ever because of online realtors. With just a click of a button, you’ll get high-quality fruiting blocks, sawdust spawns, or wood spawns ready to inoculate outdoor logs.
With these growing methods, you’ll enjoy bountiful harvests at home or in the garden. Try using all the growing methods at once and see what works best for you. You’ll have the freedom to grow a multitude of tasty varieties throughout the year.
In the end, the best mushroom-growing methods depend on what you’re growing, how big of a harvest you want, and the seasons. Everything else depends on your personal preferences. So, start experimenting to see what you can grow at home.