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Why have I got mushrooms in my seedlings?

We are using biodegradable plant pots for a lot of our new seedlings and and we are seeing lots of mushrooms sprouting up along the edges and sides, so we have done a lot of research around this!

Having mushrooms in among your seedlings is not a sign of anything sinister. We did not use seed compost for these fennel seeds as they are low maintenance, but what that will mean is there is fungal mycorrhizae that has not yet decomposed fully.

Are Mushrooms Harmful In Soil?

They cannot harm you, unless you intend to eat them. So don’t do that. Let me repeat – do not eat the mushrooms that grow in your pots!

We do not know what particular strand of mushroom they are and therefore could do all sorts of harm to you!

The role that mushrooms play in the eco-system is to start breaking down rotting wood. They are particularly good at this and are termed as early decomposers. So therefore you may still find that they are present in your compost.

Fungi that thrive on decomposing materials do not eat living plants.

Mushrooms in Scotland
This is a vibrant mushroom we saw hundreds of in the Cairngorns in September

You can buy chemically treated soils, or heated soils. These are not the solution for organic gardeners and you will find that heating the soil will in effect kill any living elements.

mushrooms are fine and not harmful to your plants

So Are Mushrooms Beneficial To My Garden?

Yes, mushrooms can be a sign of a very healthy soil. They thrive in moist, dark but warm conditions. So basically how we like to start all of our seedlings off. Our fennel seeds are not especially needy seeds. So we therefore use a good compost rather than a seed compost.

This will then result in little mushrooms. We had loads before we had even transferred them to a sunny windowsill. Now we have little mushrooms that are drying up. You can pinch them out and sling onto the compost bin.

Actually that would be an ideal thing to do as the fungi are known to release all of the stored goodness in decaying matter. For an organic garden a healthy compost heap is essential!

mushrooms don't like the sunshine
Once our fennel seedlings went on to the windowsill the mushrooms started to die off a bit.

Have I Got Fungi Because I Over Water?

Over watering is not the cause of your mushroom production. It is more to do with the issues of organic matter that has not fully composted within the soil. So do not change your plants or seedlings watering regime.

We have found that once we put the seedlings that have sprouted into daylight they disappear. First they sort of dry up and then go completely.

The actual mushroom we see is just the fruit of the fungi and the rest is still doing good work under ground. The reason a mushroom grows is because the cells are swollen with water and enlarge. This sounds like a kind of cool way to grow and I am sure that is half my problem. But we then associate the appearance of the mushrooms as a problem with too much water.

It is so important that you keep the health of your seedlings in mind as the mushrooms are not harming them, but keep that regular moisture up. Not damp or water logged but moist.

Let us know your thoughts! Love them and think they are cute? Or hate them and stay on top of pinching them out every day?

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