Is Mushroom Compost Good for a Vegetable Garden

Is Mushroom Compost Good for a Vegetable Garden?

In my ongoing quest for that “perfect vegetable garden”, I’m always on the lookout for new ways to improve my little patch of heaven. As it turns out, all vegetable gardens benefit from lots of compost and organic matter.

Compost adds nutrient-rich humus to the garden and encourages the growth of worms, beneficial bacteria, and other organisms that maintain the well-being of your garden soil. Compost added to soil is useful in retaining a healthy moisture level and breaking down clay-like deposits that may develop over time.

That being said, I have to confess: I detest the smell of compost! I have used it before and despite my best efforts, I haven’t been able to manage the odor. Fortunately, a reader suggested that I try mushroom compost as an alternative.

But what exactly is mushroom compost? How do you use it, and more importantly, is mushroom compost good for a vegetable garden?

Is Mushroom Compost Good for a Vegetable Garden?

I’ve been using 10 Pounds Sterilized Compost Mushroom Substrate which had the highest rating on Amazon and also had the greatest number of reviews at the time. Having purchased several bags, I rolled up my sleeves and got to work.

Mushroom compost slowly releases nutrients into the soil and encourages the growth of beneficial bacteria, fungus, and other micro-organisms. It also prevents the occurrence of little nasties such as pests, weeds, or viruses.

Apart from that, mushroom compost also locks moisture into the soil, making it resistant to crusting and compaction. Rain is absorbed more readily; this, in turn, encourages worms that enrich the soil further. Water runs more freely too – no more drowned or waterlogged roots!

Is Mushroom Compost Good for a Vegetable Garden?

Ultimately, mushroom compost is perfect for nearly all flowering plants, vegetables, herbs, trees (especially fruit trees), shrubs, and even lawns. Vegetable crops such as broccoli, cauliflower, cabbage, kale, kohlrabi, and Brussels sprouts are happiest in the non-acidic environment that mushroom compost brings to the soil. Potato crops also thrive due to increased moisture.

Since mushroom compost is rich in calcium, you won’t encounter the blossom-end rot which plagues a lot of tomato growers. I planned on making some compost tea to prevent leaf mold, but according to one source, the use of mushroom compost tea is dubious at best and may even be harmful.

On a side note, I think that mushroom compost looks great with its rich, dark brown colors that speak of a healthy-looking garden. 

Most importantly, mushroom compost doesn’t smell bad at all! It’s also relatively cheap compared to other traditional composts I found on the market.

What is Mushroom Compost?

Mushroom compost doesn’t contain mushrooms, even though its name suggests otherwise. Its actually the substrate left over after the process of producing mushrooms on an industrial scale. 

You’ll find that mushroom compost “recipes” vary greatly and may include chopped straw, peat moss, poultry manure, cocoa shells, cottonseed or canola meal, gypsum, potash, lime, and urea. The mixture is left for a month to allow heat and bacteria to build up, eliminating traces of weeds or other pathogens. 

The resulting mushroom substrate is first steam-sterilized then inoculated with edible commercial mushrooms. After a few rounds of harvesting, the bed is deemed “used up” for mushroom production and sold as compost.

Here’s an interesting video that demonstrates how Northway Mushrooms creates mushroom compost on an industrial level.

Potential Problems of Using Mushroom Compost

While you might find using mushroom compost to be useful, there are a few things you should know first. Some plants like fruit bushes and certain flowers like magnolia, heathers, and camellia are incompatible with the alkaline properties of mushroom compost and prefer a more acidic environment.

Fresh mushroom compost is rich in soluble salts that need to be leached out or cured before use. Excessive salt levels can harm germinating seeds and kill salt-sensitive plants such as rhododendrons, blueberries, and azaleas. Nutrient levels are low, however, relative to other forms of packaged garden manure, with most of the available nitrogen depleted by the mushrooms that previously used the compost.

Mushroom compost may contain large amounts of chalk which you should remove to prevent an accumulation of chalky deposits in the soil. Chalk deprives the soil of nutrients and may lead to a reduction in flowering or fruiting, a yellowing of foliage, and overall stunted plant development.

Also, mushroom farmers may use chemical fertilizers or employ products such as cyromazine, diflubenzuron, methoprene, Dimlin, and Diazanon to control fungus gnats and flies. They may also use chemicals such as thiabendazole, chlorothalonil, and benomyl for fungal infections. These chemicals may find their way into commercial mushroom composts; always check with your supplier!

How is Mushroom Compost Used?

You can apply the compost evenly and uniformly from one to three-inch thickness; this was tilled into the existing soil prior to seeding and planting. For established plants, it’s best to use approximately five to six inches around the base, avoiding any bark to prevent rotting.

As mentioned, fresh mushroom compost can have concentrated levels of soluble salts that can be harmful to certain plants, notably germinating seeds, seedlings, and members of the heath family. To counter this, make sure you mix it with garden soil (25-50% is recommended). You can also allow some mushroom compost to sit uncovered to “cure” over a few months before use.

Is Mushroom Compost Good for a Vegetable Garden?

I also had success in using mushroom compost as a mulch which was great in controlling weeds and helping my garden soil retain its moisture during dry periods.


I can wholeheartedly recommend mushroom compost for vegetable gardens. However, you just have to keep these pointers in mind:

  • Don’t use mushroom compost with plants that prefer acidic soil
  • Mix mushroom compost with garden soil
  • Buy only from trusted suppliers; avoid unwanted chemicals and by-products!

The results I had from 10 Pounds Sterilized Compost Mushroom Substrate were extremely satisfying. I have a noticeable decrease in watering expenses, and most importantly, my plants and vegetables are all happy and healthy.

Please comment below and let me know if you have any questions or suggestions. My take is that if you are interested in improving the state of your vegetable garden, consider adding mushroom compost to your soil. Your garden will thank you for it!