I have always gotten mycorhizzal shrooms in my raised beds after I amend them. They never seem to hurt anything and I seem to always get a bigger crop out of the beds that I see them in than the ones I do not... not all fungi are bad for your plants, some your plants actually need to survive... Don't act in haste, make sure you get your fungi identified properly before taking any action.

Since mushrooms are fungi and there also are some bad fungi that are known collectively as "damping off" and those bad fungi do kill seedlings, I'd be concerned that my flats might have the right growing conditions for fungi. Therefore, if they were my flats of seedlings,I'd be sure I'm not keeping the growing medium too moist and I'd be sure the room has good air circulation, whether by opening a window enough to get some good air flow or by running a fan in the seedling's room.

Mushrooms aren't going to hurt your plants, but if the bad fungi that cause damping off appear, they will hurt them, so try to alter your growing conditions so it doesn't happen.

I would also try to put them in the sun for a little while if your weather will permit.

If you want to post a picture of the shrooms in question that might assist in identification.

Had to wait until I got home. Sorry for the size, I was too lazy to figure out how to shrink the pics.

Fungi are interesting things--most of the organism is invisible, the mushrooms are just the fruit. Removing the mushrooms to get rid of the fungus is like picking apples to remove an apple tree. The fungus lives in the soil, as a network of thread-like cells.

Your fungus appears to be a Coprinus species, a group that generally likes very rich organic matter. They probably won't harm your seedlings. As other people said, they may be an indication that the soil is too wet, and drying it out will help stop fungal activity.

Hope this helps!

Thanks. I did pick all the larger pieces out just in case, but good to know it isn't dangerous. I've got a fan in the room now, so maybe that'll help with drying things some.

I found this in one of my chilli Seedling pot (planted 3 weeks ago), and I have been told it's a mushroom. I would like to find out if this is an edible mushroom, or a poisonous one. Please help me. P.S I live in Cape Town and am keeping my seedlings under incandescents 24-7 until I can get my grow light after the lockdown ends.

For a mushroom ID, you need a local expert who is experienced in local mushrooms to guide you. Normally the mushrooms that pop up in soil-less mixes used to raise seedlings are not fit for human consumption.