In article ,
matthewmushroom wrote:

Hello fellow gardener

I appear to have bought a contaminated batch of Asda Smartprice
compost. In repotting several plants I'm now seeing the prolific
fruition of a cream to brown coloured fungus. A mass influx of tiny
off-white protrusions from the soil of my houseplants became heavy
clusters of diarrhoea coloured fungus, up to 3 cm diameter, close to
the base of the afficted plants. These 'shrooms are showing no mercy.

I suspect we are dealing with the famous "Honey Fungus", but am in need
of some closure. I'd be eternally grateful for some expert advice on the
subject. I have several images which I can email.

Thanks for reading.

If you send me the pictures, I can probably identify the mushrooms, at
least to Genus.

It's common for mushrooms to pop up in new potting soil. Colonies of
fungal filaments called mycelia grow in the soil and when a sufficient
mass is reached, produce fruiting bodies which are the mushrooms you
see. The Honey Fungus colonizes large rotting roots of living trees and
requires a substantial amount of substrate to form a fruiting colony, so
is not likely to be the one you are dealing with.

Mushroom fungus fruits by producing primordial fruiting bodies near the
top of the soil which take up water quickly and expand to full size in a
matter of a few days. By simply stirring the top 1/2-1" of soil with a
spoon or your fingers every few days you will disturb the formation of
these primordia and prevent mushroom fruiting. Some species require
light to form mushrooms and placing a layer of something like coarse
gravel over the soil may inhibit mushroom formation

Most of the lignophilic and coprophilic mushroom species volunteering in
commercial potting soils are not likely to interfere with the health of
your plants. The big problem with these contaminated soils is the
potential for "damping off" of seedlings when used for germination.

Most likely you will be fine if you do nothing. The fungus will deplete
the levels of nutrients it requires to produce mushrooms within a flush
(periodic display of fruiting bodies) or two, and the mycelium will die.
The fungus is not competing with your plants for nutrients in the soil.
On the contrary, mushroom fungi are primary decomposers whose role in
nature is to break down complex organic matter and make simple nutrients
available for plants and, eventually, other life forms.