When does bush rue bloom in California?

Most often in March. Across 266 dated, research-grade observations of Cneoridium dumosum in California, the flowering season runs roughly January to March.

Peak March In flower 266 Examined 487 State California

Flowering 266 in flower of 487 examined

Proportion of examined Cneoridium dumosum in California in flower, by month
Month In flower Examined Share 95% interval
Jan 41 53 77% 64% to 87%
Feb 39 54 72% 59% to 82%
Mar 88 102 86% 78% to 92%
Apr 46 76 61% 49% to 71%
May 20 66 30% 21% to 42%
Jun 1 31 3% 1% to 16%
Jul 0 22 0% 0% to 15%
Aug 0 10 0% 0% to 28%
Sep 3 13 23% 8% to 50%
Oct 2 14 14% 4% to 40%
Nov 3 4 too few examined
Dec 23 42 55% 40% to 69%

Peak flowering in Mar. Each bar is the share of Cneoridium dumosum 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. 266 of 487 examined observations were in flower, every one of them research grade. The whisker on each bar is a 95% Wilson interval. One month has fewer than 5 examined observations, so no proportion is drawn for it. 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 Cneoridium dumosum 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

Sourcesevery claim on this page

  1. 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.
  2. World Flora Online Plant List. The accepted name. CC0. Retrieved 2026-07-12.