When does dyebush bloom in California?

Most often in May. Across 508 dated, research-grade observations of Psorothamnus emoryi in California, the flowering season runs roughly April to December.

Peak May In flower 508 Examined 702 State California

Flowering 508 in flower of 702 examined

56%

46%

68%

83%

100%

90%

100%

97%

90%

84%

Proportion of examined Psorothamnus emoryi in California in flower, by month
Month	In flower	Examined	Share	95% interval
Jan	49	87	56%	46% to 66%
Feb	58	125	46%	38% to 55%
Mar	109	160	68%	61% to 75%
Apr	70	84	83%	74% to 90%
May	29	29	100%	88% to 100%
Jun	9	10	90%	60% to 98%
Jul	3	4	too few examined
Aug	4	4	too few examined
Sep	12	12	100%	76% to 100%
Oct	34	35	97%	85% to 99%
Nov	55	61	90%	80% to 95%
Dec	76	91	84%	75% to 90%

Peak flowering in May. Each bar is the share of Psorothamnus emoryi 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. 508 of 702 examined observations were in flower, every one of them research grade. The whisker on each bar is a 95% Wilson interval. 2 months have fewer than 5 examined observations, so no proportion is drawn for them. 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 Psorothamnus emoryi 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

Psorothamnus emoryi

dyebush

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.