Mushroom compost for the garden has been promoted as beneficial for some time now, but it’s important to note that not every plant reaps the benefits of mushroom compost. What plants don’t like mushroom compost? Acid loving plants, for one. Is mushroom compost good for a vegetable garden? The following contains information on plants that do and don’t like mushroom compost and how to use it in your garden.
What is Mushroom Compost?
Sold packaged at garden supply centers or in bulk from mushroom growers themselves, mushroom compost is specially mixed compost most suited for commercial growing of mushrooms. It’s sold when it is “spent,” meaning after a round of mushrooms has been grown in it and it is beginning to lose some of the nutrients specific to the optimal growth of the fungi.
Just because mushroom compost is spent doesn’t mean it has no value. In fact mushroom compost is incredibly good for most but not all of the garden.
What is in mushroom compost? The recipe for mushroom compost varies depending upon the company, but it may contain wheat or rye straw, peat moss, used horse bedding straw, chicken manure, cottonseed or canola meal, the leavenings from grape pressing, soybean meal, potash, gypsum, urea, ammonium nitrate and lime.
The concoction is mixed up and then allowed to sit for about 30 days to heat up and begin the composting process. Straw provides the basis for the compost and some nourishment for beneficial bacteria and the chicken manure, while cottonseed meal and urea provide additional nutrition. The bacteria feed and multiply, raising the temp of the compost pile enough to kill any weed seeds or pathogens. The resulting compost is then ready to grow mushrooms in.
What is Mushroom Compost Good For?
Mushroom compost improves water retention, improves soil structure, has a mild nitrogen content which means it provides a slow uptake for plants but low enough to discourage weed growth, attracts earthworms, effectively insulates cooling or warming roots according to the season, and is an excellent slow release fertilizer.
What Plants Don’t Like Mushroom Compost?
Because mushroom compost is great at improving water retention, it isn't a good option for plants that don’t like “wet feet” such as succulents. This increase in water retention can also lead to rot or fungal infections.
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Mushroom compost may be alkaline due to its high content of chalk or lime. But not all mushroom compost will be alkaline, so it is best to do a pH test prior to use, especially around acidic loving plants.
Mushroom compost is also high in salt, which can be problematic for some plants such as blueberries, camellias, rhododendrons and azaleas. These soluble salts along with other nutrients in fresh mushroom compost are too concentrated to germinate seeds or plant young seedlings.
If you have mushroom compost and are unsure of its content, it's best to mix it with garden soil prior to use on young plants. Or better yet, procure your compost in the fall and allow it to sit and cure over the winter months.
Although mushroom compost attracts earthworms, at the outset it lacks beneficial microorganisms. This is because the spent product has been pasteurized prior to sale in order to kill weed seeds, pests or pathogens.
How to Use Mushroom Compost
You can either procure your mushroom compost by the bag or order it in bulk. When used after curing or when mixed with garden soil, mushroom compost can be used around perennials, trees, and shrubs. In the vegetable garden, till three inches (8 cm) of compost into the top six inches (15 cm) of dry soil.
Mushroom compost can be used in container grown plants as well, but only at the rate of 1 to 4, compost to soil.
FAQs
Just because mushroom compost is spent doesn't mean it has no value. In fact mushroom compost is incredibly good for most but not all of the garden.
Is mushroom compost suitable for all plants? ›
Mushroom compost is suitable for most garden plants. It supports various types of plant growth, from fruits and vegetables to herbs and flowers. To get the greatest results when organic gardening with mushroom compost, thoroughly mix it in with the garden soil prior to planting.
What are the cons of mushroom compost? ›
Factors To Consider When Using Mushroom Compost
Farmers should use the compost with caution due to its high salinity. The high salt levels can kill and harm young and germinating seeds. They also cause damage to plants that are salt-sensitive such as blueberries and azaleas.
What to use instead of mushroom compost? ›
Environmentally Friendly Alternative:
Thankfully, there is a more environmentally friendly option available: green waste compost. This process involves using organic waste such as leaves and grass clippings to create nutrient-rich compost.
Does mushroom compost have a lot of nitrogen? ›
Mushroom compost contains an average of 1.12 percent nitrogen in a mostly organic form that slowly is available to plants.
What plants do not like mushroom compost? ›
Mushroom compost is also high in salt, which can be problematic for some plants such as blueberries, camellias, rhododendrons and azaleas. These soluble salts along with other nutrients in fresh mushroom compost are too concentrated to germinate seeds or plant young seedlings.
Can I use mushroom compost instead of soil? ›
Mushroom compost needs to be mixed with soil and should not be used alone to grow plants in. If you are amending your soil with neat mushroom compost, you should mix it in at a ratio of one part compost to two parts soil.
Do tomatoes like mushroom compost? ›
Mushroom soil also contains more calcium than regular compost due to the addition of chalk. Plants like tomatoes do well in a calcium-rich soil which helps tamp down blossom-end rot.
Can I use too much mushroom compost? ›
Mushroom compost can supply nutrients and increase water-holding capacity of the soil. But mushroom compost can also be too much of a good thing for seeds, seedlings and young plants.
Which is better, mushroom compost or manure? ›
Easy to use and apply: While cow manure is heavier, mushroom compost is lighter and easier to spread. While some plants may be more sensitive to the salt content in fresh mushroom compost, there's less chance of spreading pathogens when using this compared to using fresh manure.
Mushroom soil or mushroom compost is a great organic amendment for enriching the soil used to grow fruits, vegetables, and even flowers.
What is the best compost for vegetable gardens? ›
Loam Based Compost
Loam-based compost is a combination of soil, sand, and clay that has been decomposed and processed to create a deep, rich product that is ideal for growing vegetables. Loam-based compost can be purchased commercially or created at home using a simple composting bin.
How long does mushroom compost last? ›
You may use spent compost weathered for 6 months or longer in all gardens and with most plants. Obtaining mushroom compost in the fall and winter, allowing it to weather will make it ready to use in a garden the following spring. Spring and summer are the best time to use weathered material as a mulch.
What are the disadvantages of mushroom compost? ›
Disadvantages of using mushroom compost
One of the biggest concerns about mushroom compost in the garden is that it tends to have high levels of salt, which can be detrimental to most plants in large quantities, and potentially deadly to seedlings and young plants.
Do weeds grow in mushroom compost? ›
Pros of mushroom compost
Plus, it is considered to be a soil improver due to its ability to retain moisture and prevents waterlogged roots. Therefore, it's great to use around moisture loving plants, as well as it enriches the soil's texture and helps to regulate weed growth.
Is mushroom compost better than worm castings? ›
To summarize, both products are a good supply of organic matter. Plants grown in good soil-applied to either of these products are healthy. However, to answer the question of mushroom compost vs worm castings, mushroom compost is the best choice due to its less time-consuming nature.
What plants are best for mushroom compost? ›
Mushroom compost is excellent on the vegetable garden, as vegetable crops usually grow best when th soil is not acid and where the soil is alkaline brassicas (cabbage, broccoli, cauliflower, kohlrabi, Brussels sprouts and kale) are less likely to be infected by clubroot disease.
Is mushroom compost good for tomato plants? ›
Certain vegetables particularly thrive in mushroom compost due to its rich nutrient content. These include tomatoes, zucchinis, pumpkins, and root vegetables such as carrots and radishes. The nutrients in mushroom compost can help stimulate growth, increase yield, and enhance the taste of your homegrown produce.
Do marigolds like mushroom compost? ›
Suitable flowers: Many ornamental flowers, such as marigolds, zinnias, and sunflowers, can thrive in soil amended with mushroom compost.
