People who want to improve their soil with nutrients and organic matter often use mushroom compost. But is adding mushroom compost to your garden helpful for growing potatoes? This in-depth article will look at the pros and cons of using mushroom compost for potatoes.
What is Mushroom Compost?
Mushroom compost, which is also known as “spent mushroom substrate,” is made from the growing medium that is left over after mushrooms are sold. The original ingredients depend on the company that makes it, but they usually include corn, cottonseed, peat moss, straw, and chicken manure.
After the mushroom crop is harvested, the remaining compost is pasteurized to kill off any fungi or bacteria. This destroys lingering pathogens while leaving beneficial microorganisms. The finished compost contains a diverse blend of organic materials and nutrients.
Potential Benefits of Mushroom Compost for Potatoes
When used properly, mushroom compost offers some potential upsides for growing hearty potato crops:
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Organic matter – The compost introduces beneficial organic materials like straw, peat, and manure This can improve soil structure, aeration, and water retention
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Mushroom compost has many macronutrients, such as nitrogen, phosphorus, and potassium, which come from the manure and organic materials that were used to make it. This helps feed soil microbes and potato plants.
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Soil life – The compost contains microorganisms like beneficial bacteria and fungi. These help break down organic matter and cycle nutrients for plant availability.
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Moisture retention – The peat, straw, and other organic materials in mushroom compost act like a sponge to hold moisture. Potatoes need consistent soil moisture.
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Weed suppression – Spread as mulch, mushroom compost can block light and smother weed seed germination. Less weeding means less root/tuber damage.
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pH level—Mushroom compost has a pH level of about 6 that is neutral to slightly alkaline. 5-7. 5. This is the preferred pH for potatoes, counteracting acidic soils.
Potential Drawbacks of Using Mushroom Compost on Potatoes
However, there are also some possible disadvantages to keep in mind:
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Salt content – Some mushroom compost contains high salt content from the manure and other amendments used. Excess salts can damage plant roots.
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Depleted nutrients – Since it already grew mushrooms, nitrogen and other nutrients can be depleted in mushroom compost. Additional fertilizer may be needed to replenish.
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Fast drying – The added organic matter can lead mushroom compost to dry out quickly. More frequent irrigation may be required in hot/dry weather.
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Weed seeds – Lower quality mushroom compost may harbor viable weed seeds that will sprout unwanted plants.
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Mold issues – If not fully pasteurized, active mold and fungi can remain in mushroom compost and spread issues like blight.
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Cost – Purchased mushroom compost is typically more expensive than making your own compost at home.
Best Practices for Using Mushroom Compost on Potatoes
To maximize the benefits while avoiding potential problems, follow these tips:
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Test new mushroom compost for pH, salt content, and pathogens before using in your garden.
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Mix compost with garden soil or coconut coir at a 1:1 ratio for better drainage and nutrient balance.
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Till compost into potato rows, not directly on seed potatoes which can burn tender sprouts.
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Water newly planted potatoes daily until sprouts emerge to account for moisture loss through compost.
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Side dress growing potato plants halfway through the season with extra compost as a moisture retaining mulch.
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Avoid mushroom compost sources that result in disease or fungi issues. Discontinue their use.
The Verdict: Can Mushroom Compost Help Potatoes Thrive?
When used properly by testing its quality first, mushroom compost can be a beneficial addition for enriching and nourishing potato crop soils. Its moisture retention and organic matter are useful, but should be balanced with extra fertilizer and close irrigation to prevent deficiencies. With smart practices, mushroom compost can absolutely help your potatoes thrive! But farmers should always assess each new batch of compost for quality and blend accordingly into their beds or rows.
Sit Back & Let Your Potatoes Grow
Potatoes do take quite a long time to form. Remember they have to literally multiply themselves underground. I generally plant my potatoes in April and dont harvest them until August, which is about 90 to 100 days after planting.
For culinary purposes, you can classify potatoes as vegetables. Thats a really broad category though, and it doesnt tell us gardeners very much about how to actually grow potatoes.
So for gardening purposes, were going to classify potatoes as a root crop. Potatoes are technically tubers, meaning theyre fleshy underground stems that grow new plants through buds. Similar to roots, tubers store nutrients for the entire potato plant.
I lump potatoes and sweet potatoes (which are tuberous roots) in with roots like carrots, beets, and radishes for one obvious reason: The part we want to eat grows underground. Also, if you know how to grow one, you’ll know how to grow the others much better.
Prepare the Space for Your Potato Plants
Potatoes prefer more acidic dirt. You can buy acidifiers to amend your garden soil, but I’ve found that potatoes planted in compost grow totally tubular, as well. Add about two to three inches of compost in the trench. I use Espoma’s Organic Mushroom Compost. This way, when potatoes are planted for the first time, they’ll feel like they’re in full compost, which is great for them. Shop Gardening Books.
Is Mushroom Compost Good For A Garden Or Should You Avoid It?
FAQ
Can I use mushroom compost on potatoes?
Prepare the Space for Your Potato Plants Add about two to three inches of compost in the trench. I use Espoma’s Organic Mushroom Compost. This way, when potatoes are first planted, they’ll feel like they’re in 100 percent compost, which will give them a great start.
What is the best compost for potatoes?
For growing potatoes, a good compost choice is a well-rotted manure-based compost, or a peat-free multi-purpose compost mixed with John Innes. Potatoes benefit from a soil that is rich in nutrients, well-draining, and slightly acidic.
Which plants do not like mushroom compost?
4. Do not apply hot compost (meaning mushroom compost or other nutrient rich sources) to woodland (eg ferns) or silver-leaved plants (lavender), because they are not used to having that level of nitrogen shock. Instead, use leaf litter for the woodland.
When should you not use mushroom compost?
Mushroom compost use should be avoided where ericaceous plants such as rhododendrons, camellias, azaleas and heathers are being grown, as these plants need acidic growing conditions and are chalk-hating.