Planted onion bulbs about 3 weeks ago. I have them in a container in the house at the window. Other things have started to grow in the soil. They have stems about 2" and a top like a mushroom, and when I touch them they just stick to my hand.
Things Growing in My Soil Pot Beside My Onion Bulbs
Certified GKH Gardening Expert
It's likely a fungus of some sort. This article will help you: https://www.gardeningknowhow.com/houseplants/hpgen/getting-rid-of-mushrooms-growing-in-houseplant-soil.htm
I've had good luck getting rid of mushrooms simply by digging them up with a spoon as soon as they appear. Try scraping off the top 2 or 3 inches of soil and replacing it with sand. And don't use any more of that soil, it was probably contaminated. Also, mushrooms thrive in moist conditions, so double check your watering, and put the pot where it gets more light, if you can. And be sure to wash your hands if you touch the things, they may may be poisonous. I would not recommend fungicide.