When does California Buckwheat bloom in California?

Most often in July. Across 3,066 dated, research-grade observations of Eriogonum fasciculatum in California, the flowering season runs roughly May to August.

Peak July In flower 3,066 Examined 4,267 State California

Flowering 3,066 in flower of 4,267 examined

63%

62%

60%

63%

78%

93%

94%

85%

65%

64%

69%

62%

Proportion of examined Eriogonum fasciculatum in California in flower, by month
Month	In flower	Examined	Share	95% interval
Jan	262	415	63%	58% to 68%
Feb	225	365	62%	57% to 66%
Mar	238	399	60%	55% to 64%
Apr	295	470	63%	58% to 67%
May	430	553	78%	74% to 81%
Jun	457	492	93%	90% to 95%
Jul	310	331	94%	91% to 96%
Aug	194	229	85%	79% to 89%
Sep	167	256	65%	59% to 71%
Oct	155	242	64%	58% to 70%
Nov	119	172	69%	62% to 76%
Dec	214	343	62%	57% to 67%

Peak flowering in Jul. Each bar is the share of Eriogonum fasciculatum 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. 3,066 of 4,267 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 Eriogonum fasciculatum 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

Eriogonum fasciculatum

California Buckwheat

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.