Mycoscout How to identify St George's mushroom
St George's mushroom (Calocybe gambosa) is the first substantial edible of the British spring: a stout, white to cream mushroom with a thick, often lopsided cap, very crowded white gills, a short solid stem with no ring, and a strong smell of fresh flour. It grows in grass, often in rings, from April into June. The one dangerous confusion is the deadly fibrecap, which arrives at woodland edges as St George's season ends and whose cap, gills and stem all slowly stain red.
| Feature | St George's mushroom |
|---|---|
| Cap | 5–15 cm (First Nature, Wildlife Trusts); 6–10 cm typical (Wild Food UK). White to cream, turning buff or tan with age; smooth, often misshapen, with an incurved margin; the surface cracks as it ages. |
| Gills | White to pale cream, narrow, very crowded, notched (sinuate) where they meet the stem. |
| Stem & base | 3–7 cm tall, 2–4 cm thick (First Nature), solid, stout, often curved and a little thicker at the base. No ring, no sac. |
| Flesh | Firm and white; prone to maggots as it ages. |
| Spore print | White. |
| Smell | Strong, mealy or floury; sometimes cucumber-like (Wildlife Trusts). Mostly lost on cooking. |
| Habitat | Cropped pasture, lawns, roadside verges and field edges near hedges and deciduous trees (hazel, beech, oak, birch); occasionally in mixed woodland. Common on chalk and limestone. Often in rings. |
| Season | April–June in Britain and Ireland (First Nature); April–May (Wildlife Trusts, Wild Food UK). About a month earlier in southern Europe; June–July in Scandinavia. |
| Range (US / UK & Europe) | UK: "fairly frequent throughout Britain" (NatureSpot). Europe: Italy's marzolino, Germany's Maipilz. US: none of the sources we checked covers North America; treat a white spring mushroom there as unknown. |
Confirm these features
- Strong smell of flour or meal from the fresh mushroom. No smell, or a sweet or unpleasant one, means stop.
- Gills white to cream, very crowded, notched at the stem; not pink, not brown, not running down the stem.
- Spore print white.
- Stem short, solid and stout, with no ring and no sac or bulb at the base.
- Cap smooth, not silky or streaked with radial fibers; no red or pink staining anywhere after handling or cutting. Wait a few minutes and look again.
- Season April to June, in grass or at a field or wood edge, often in a ring.
Why one feature is never enough: "white and in grass in spring" also describes a young deadly fibrecap at the edge of a wood, and the red stain is slow. The miller smells mealy too. Only the combination of smell, white print, crowded notched gills, ringless stem and no red staining adds up to St George's mushroom.
Dangerous look-alikes
Deadly fibrecap, red-staining fibrecap (Inosperma erubescens, formerly Inocybe erubescens)
Tell apart: the cap is 3–7 cm (First Nature) to 4–10 cm (Wild Food UK), ivory to cream, silky, with streaky radial fibers that split at the edge, and a pointed bump at the center. The gills start whitish but turn pinkish brown from the margin inward, and the spore print is dull brown. Cap, gills and stem fibers all stain red slowly when bruised; Wild Food UK says the stem "slowly turns vivid red when touched". It grows under beech and hornbeam on chalk, singly or in small groups, mainly at woodland edges in southern England; First Nature gives late June to September, Wild Food UK May to September, so it overlaps the end of St George's season. First Nature's St George's page notes the fibrecap's gills are "pale pink rather than white" and "turn red when bruised". St George's mushroom has a smooth cap, white gills, a white print and never stains red. Risk: deadly. It contains muscarine, and First Nature describes it as the fibrecap "known conclusively to have caused deaths". Symptoms begin within 15–30 minutes (NAMA) to two hours (Frontiers in Microbiology, 2022): sweating, salivation, tears, blurred vision, severe vomiting and diarrhea, and in severe cases respiratory failure. Get help now; do not wait.
The miller (Clitopilus prunulus)
Tell apart: also white and mealy-smelling, but its gills run down the stem (decurrent) rather than being notched, and First Nature says it appears later in the year. Risk: our sources do not list the miller as poisonous, but they do not cover its own look-alikes either, so it is not a mushroom to pick on the strength of this page.
White Amanitas and other white-gilled, ringed mushrooms
Tell apart: St George's mushroom has no ring and no sac at the base. A white mushroom with a skirt-like ring or a cup at the base is an Amanita and may be a destroying angel, though those fruit from summer rather than spring. Risk: deadly. Dig the whole base before deciding.
Where and when it grows
This is a grassland species with a taste for lime. First Nature lists cropped pastures near deciduous trees, mown verges by hedges and, occasionally, mixed woodland, most often near hazel, beech, oak and silver birch, and notes it is common in chalk and limestone districts but also found on moderately acidic grassland. The Wildlife Trusts add arable fields, urban roadsides and an association with hawthorn, and warn that a small group may be part of a fairy ring many meters wide that returns to the same spot each year.
It fruits from around 23 April, St George's Day, which gives it its name, though NatureSpot and the Wildlife Trusts both say it often matures a little later; First Nature gives April to June for Britain and Ireland, a month earlier in southern Europe and into July in Scandinavia. It is fairly frequent throughout Britain. Our sources are all British and European; we found no reputable North American source for this species, so the US range is not covered here.
Before you eat any
First Nature calls it a good edible and Wild Food UK rates its taste "good, mushroomy", losing most of its mealy character when cooked. Wild Food UK says it "must be cooked before consumption"; First Nature notes a reputation for being eaten raw, but its author always cooks it; so should you. Cut each one vertically to check for maggots, which both sources say are common in older caps. Avoid busy roadside verges, where First Nature warns the soil may hold pollutants. Then do what every source says: confirm your first finds with a local mycological society or an experienced forager, and take a spore print of a few from each ring.
Using an app to check a find
A photo can show the cream cap, the crowded white gills and the ringless stem, which rules out a lot. It cannot show the floury smell, the white print, or the slow red stain that separates a young deadly fibrecap. Mycoscout leads with the edibility verdict, shows its confidence, names the deadly fibrecap as the look-alike to rule out and tells you which features to check by hand. It is a field companion, not a clearance to eat; a spring edible is only worth picking once an expert has confirmed it. More about the app at Mycoscout.
Frequently asked questions
When does St George's mushroom grow?
April to June in Britain and Ireland, named for St George's Day on 23 April, though it often matures a little later. First Nature puts it about a month earlier in southern Europe and as late as June and July in Scandinavia.
What does St George's mushroom smell like?
Strongly of flour or meal when fresh; the Wildlife Trusts add that it is often cucumber-like too. Cooking removes most of the smell. A spring mushroom without that smell should be treated as something else.
What are the look-alikes of St George's mushroom?
The deadly fibrecap (Inosperma erubescens), which fruits at woodland edges from late spring, has a silky, radially fibrous cap, gills that turn pinkish brown, a dull brown spore print and flesh that slowly stains red. The miller (Clitopilus prunulus) also smells mealy but has gills running down the stem and fruits later in the year.
Can you eat St George's mushroom raw?
Wild Food UK says it must be cooked before eating. First Nature notes a reputation for being eaten raw, but its author always cooks it. Cook it, and never eat any wild mushroom you have not had confirmed by an expert.
Sources
How we checked this page: the Mycoscout team cross-checked every edibility, toxicity and look-alike statement against the sources below on October 31, 2026. It has not been reviewed by a mycologist.
- Calocybe gambosa, St George's Mushroom, First Nature. Accessed October 31, 2026.
- St George's mushroom, The Wildlife Trusts. Accessed October 31, 2026.
- St George's Mushroom, Calocybe gambosa, NatureSpot. Accessed October 31, 2026.
- St. George's Mushroom (Calocybe gambosa), Wild Food UK. Accessed October 31, 2026.
- Inocybe erubescens, Deadly Fibrecap, First Nature. Accessed October 31, 2026.
- Deadly Fibrecap (Inosperma erubescens), Wild Food UK. Accessed October 31, 2026.
- Mushroom poisoning syndromes, North American Mycological Association. Accessed October 31, 2026.
- A new muscarine-containing Inosperma species discovered from one poisoning incident in tropical China, Frontiers in Microbiology (2022). Accessed October 31, 2026.
