When does Creosote Bush bloom in California?

Most often in April. Across 2,548 dated, research-grade observations of Larrea tridentata in California, the flowering season runs roughly March to April.

Peak April In flower 2,548 Examined 6,008 State California

Flowering 2,548 in flower of 6,008 examined

25%

46%

66%

75%

58%

17%

16%

17%

16%

31%

23%

Proportion of examined Larrea tridentata in California in flower, by month
Month	In flower	Examined	Share	95% interval
Jan	286	1125	25%	23% to 28%
Feb	389	837	46%	43% to 50%
Mar	809	1217	66%	64% to 69%
Apr	502	667	75%	72% to 78%
May	180	309	58%	53% to 64%
Jun	24	144	17%	11% to 24%
Jul	5	77	6%	3% to 14%
Aug	18	111	16%	11% to 24%
Sep	34	206	17%	12% to 22%
Oct	66	413	16%	13% to 20%
Nov	101	331	31%	26% to 36%
Dec	134	571	23%	20% to 27%

Peak flowering in Apr. Each bar is the share of Larrea tridentata 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. 2,548 of 6,008 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 Larrea tridentata 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

Larrea tridentata

Creosote Bush

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.