When does California poppy bloom in California?

Most often in August. Across 6,881 dated, research-grade observations of Eschscholzia californica in California, the flowering season runs roughly February to November.

Peak August In flower 6,881 Examined 7,164 State California

Flowering 6,881 in flower of 7,164 examined

79%

94%

96%

97%

98%

99%

95%

93%

82%

70%

Proportion of examined Eschscholzia californica in California in flower, by month
Month	In flower	Examined	Share	95% interval
Jan	113	143	79%	72% to 85%
Feb	476	507	94%	91% to 96%
Mar	1365	1416	96%	95% to 97%
Apr	1964	2016	97%	97% to 98%
May	1213	1242	98%	97% to 98%
Jun	604	618	98%	96% to 99%
Jul	375	382	98%	96% to 99%
Aug	273	276	99%	97% to 100%
Sep	203	213	95%	92% to 97%
Oct	139	149	93%	88% to 96%
Nov	100	122	82%	74% to 88%
Dec	56	80	70%	59% to 79%

Peak flowering in Aug. Each bar is the share of Eschscholzia californica in California observations in which someone actually recorded the reproductive state and found the plant in flower, not the raw number of flowering records. That distinction matters: people observe plants far more in spring than in winter, so a bare count of flowering records partly measures when people go outside. Dividing by the number examined removes that. 6,881 of 7,164 examined observations were in flower, every one of them research grade. The whisker on each bar is a 95% Wilson interval. This is still a global aggregate and not a forecast for your garden: the same species flowers on different dates in different hemispheres. Where a species has fewer than 30 flowering records we do not draw this chart at all. Computed from 10.15468/dl.wt38fd.

What this is, and what it is not

This is a record of when people in California found Eschscholzia californica in flower, not a forecast. It is computed only from observations made in California, so it is not the species’ global average dragged onto a map: the same plant flowers on different dates in different places, and that is the entire point of the page.

It will not tell you what your particular plant will do this year. Bloom time moves with the season, with altitude, and with the weather, and a warm February pulls everything forward. We publish the distribution and the sample size, and we refuse to draw a month that too few people examined.

The plant

Eschscholzia californica

California poppy

Sourcesevery claim on this page

GBIF (iNaturalist Research-grade Observations). Dated flowering annotations in California. Every record achieved iNaturalist quality grade Research, which is applied upstream at export. 10.15468/dl.wt38fd. Retrieved 2026-07-14.
World Flora Online Plant List. The accepted name. CC0. Retrieved 2026-07-12.