When does coyote brush bloom in California?

Most often in October. Across 3,114 dated, research-grade observations of Baccharis pilularis in California, the flowering season runs roughly August to November.

Peak October In flower 3,114 Examined 6,205 State California

Flowering 3,114 in flower of 6,205 examined

28%

18%

27%

65%

66%

77%

69%

44%

Proportion of examined Baccharis pilularis in California in flower, by month
Month	In flower	Examined	Share	95% interval
Jan	115	413	28%	24% to 32%
Feb	35	196	18%	13% to 24%
Mar	7	219	3%	2% to 6%
Apr	3	445	1%	0% to 2%
May	2	213	1%	0% to 3%
Jun	5	157	3%	1% to 7%
Jul	58	211	27%	22% to 34%
Aug	279	429	65%	60% to 69%
Sep	647	982	66%	63% to 69%
Oct	950	1231	77%	75% to 79%
Nov	723	1046	69%	66% to 72%
Dec	290	663	44%	40% to 48%

Peak flowering in Oct. Each bar is the share of Baccharis pilularis 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. 3,114 of 6,205 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 Baccharis pilularis 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

Baccharis pilularis

coyote brush

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.