National Mushroom Month 2027 runs from Wednesday, September 1, to Thursday, September 30, 2027. The month has been proclaimed every September since 1992, with roots in the Mushroom Festival in Kennett Square, Pennsylvania.
National Mushroom Day is a separate day, and its date depends on who you ask: October 15 for the Mushroom Council, or June 1 in a 2026 Senate resolution.
Key takeaways
- National Mushroom Month is September every year; in 2027, it runs from Wednesday, September 1, to Thursday, September 30.
- National Mushroom Day is October 15, according to the Mushroom Council, which falls on a Friday in 2027.
- Pennsylvania grew 74% of US Agaricus mushrooms by volume in the 2025–2026 season.
- The white button, cremini, and portobello are all the same mushroom, Agaricus bisporus, the most eaten mushroom in the US.
National Mushroom Month 2027 at a glance
- Dates: Wednesday, September 1 – Thursday, September 30, 2027.
- Proclaimed since: 1992, by the US Secretary of Agriculture and the Governor of Pennsylvania.
- Supported by: the Mushroom Council, the growers’ research and promotion board.
- National Mushroom Day: Friday, October 15, 2027 (Mushroom Council).
- Top producing state: Pennsylvania.
Table of Contents
When is National Mushroom Month 2027?
National Mushroom Month 2027 is September 1–30, 2027. It starts on a Wednesday and ends on a Thursday, and falls at the start of the fall mushroom season.
When is National Mushroom Day?
National Mushroom Day is October 15, according to the Mushroom Council, the industry board for US mushroom growers (Mushroom Council). In 2027, October 15 falls on a Friday.
A second date has been proposed. On April 16, 2026, Senators John Fetterman and Dave McCormick of Pennsylvania introduced Senate Resolution 676, which recognizes June 1 as National Mushroom Day (GovInfo).
The resolution was referred to the Senate Agriculture Committee, so check whether it has passed before relying on the June date.
| Observance | Date | 2027 | Source |
|---|---|---|---|
| National Mushroom Month | September | Wednesday, September 1 – Thursday, September 30 | Proclaimed since 1992 |
| National Mushroom Day | October 15 | Friday, October 15 | Mushroom Council |
| National Mushroom Day (proposed) | June 1 | Tuesday, June 1 | Senate Resolution 676 (2026) |
Is there an International Mushroom Day? There is no widely recognized international or UN mushroom day. Most mushroom observances are national, led by growers and food groups.
How did National Mushroom Month start?
National Mushroom Month grew out of the Mushroom Festival in Kennett Square, Pennsylvania. Starting in 1992, the US Secretary of Agriculture and the Governor of Pennsylvania issued official proclamations naming September as National Mushroom Month (Wikipedia).
The Mushroom Council, created by the Mushroom Promotion, Research and Consumer Information Act of 1990, now promotes the month. Its goal is to get people to eat mushrooms as often as other vegetables.
Kennett Square has a long history with mushrooms. According to Senate Resolution 676, the first dedicated mushroom-growing operation in the area opened in 1885, more than two centuries after mushroom cultivation began in France in 1651.
What is the most eaten mushroom in the world?
The best-known answer is Agaricus bisporus, sold as the white button mushroom, the brown cremini, and the large portobello.
All three are the same species, picked at different ages, and it is by far the most eaten mushroom in the US.
Worldwide, its lead has shrunk. Agaricus made up 56.2% of world cultivated mushroom production in 1986 but 31.8% in 1997, as shiitake and oyster mushrooms grew, mainly in Asia (Penn State). Shiitake and oyster mushrooms have kept growing since.
| Name in stores | What it is |
|---|---|
| White button | Young, white Agaricus bisporus |
| Cremini (baby bella) | Young, brown Agaricus bisporus |
| Portobello | Mature brown Agaricus bisporus with an open cap |
In the US, Agaricus mushrooms made up 620 million pounds of sales in the 2025–2026 season, worth $847 million, while specialty mushrooms such as shiitake and oyster brought in $75.0 million (FreshPlaza, reporting USDA data).
Mushrooms are fat-free, cholesterol-free, low in calories, and low in sodium, as Senate Resolution 676 notes.
Which state is number one in mushroom production?
Pennsylvania is the top mushroom-producing state. It grew 74% of all US Agaricus mushrooms by volume in the 2025–2026 season, according to the USDA (FreshPlaza).
Most of that comes from Chester and Berks Counties, which grow over 60% of the nation’s mushrooms.
Mushroom farms there employ nearly 10,000 workers and bring an estimated $2.7 billion into Chester County (Senate Resolution 676). Kennett Square calls itself the “Mushroom Capital of the World.”
How to celebrate National Mushroom Month
- Cook with a new variety: try shiitake, oyster, or maitake alongside the usual button mushroom.
- Blend mushrooms into meat: swapping part of the ground meat in burgers or tacos for chopped mushrooms adds savory flavor.
- Visit a mushroom festival: Kennett Square holds its Mushroom Festival in September.
- Join a guided foraging walk: only pick wild mushrooms with an expert, because some poisonous species look like edible ones.
- Grow your own: indoor mushroom kits produce oyster or button mushrooms in a few weeks.
National Mushroom Month dates 2026 to 2031
| Year | National Mushroom Month | National Mushroom Day (October 15) |
|---|---|---|
| 2026 | Tuesday, September 1 – Wednesday, September 30 | Thursday |
| 2027 | Wednesday, September 1 – Thursday, September 30 | Friday |
| 2028 | Friday, September 1 – Saturday, September 30 | Sunday |
| 2029 | Saturday, September 1 – Sunday, September 30 | Monday |
| 2030 | Sunday, September 1 – Monday, September 30 | Tuesday |
| 2031 | Monday, September 1 – Tuesday, September 30 | Wednesday |
Frequently asked questions
When is National Mushroom Month 2027?
National Mushroom Month 2027 runs from Wednesday, September 1, to Thursday, September 30, 2027.
What day is National Mushroom Day?
National Mushroom Day is October 15, according to the Mushroom Council. A 2026 Senate resolution proposed June 1 instead.
When is National Mushroom Day 2027?
National Mushroom Day 2027 is Friday, October 15, 2027, on the Mushroom Council’s date.
Is there an International Mushroom Day?
No widely recognized international or UN mushroom day exists. Mushroom days and months are mostly national.
What is the most eaten mushroom in the world?
Agaricus bisporus, sold as white button, cremini, and portobello mushrooms, has long been the most eaten, though shiitake and oyster mushrooms have closed the gap worldwide.
Which state is No. 1 in mushroom production?
Pennsylvania, which grew 74% of US Agaricus mushrooms by volume in the 2025–2026 season.
