When does Redwood Violet bloom in California?

Most often in April. Across 344 dated, research-grade observations of Viola sempervirens in California, the flowering season runs roughly January to July.

Peak April In flower 344 Examined 393 State California

Flowering 344 in flower of 393 examined

91%

97%

99%

100%

93%

91%

86%

71%

22%

Proportion of examined Viola sempervirens in California in flower, by month
Month	In flower	Examined	Share	95% interval
Jan	32	35	91%	78% to 97%
Feb	61	63	97%	89% to 99%
Mar	114	115	99%	95% to 100%
Apr	43	43	100%	92% to 100%
May	43	46	93%	83% to 98%
Jun	29	32	91%	76% to 97%
Jul	12	14	86%	60% to 96%
Aug	5	7	71%	36% to 92%
Sep	0	0	too few examined
Oct	0	5	0%	0% to 43%
Nov	4	18	22%	9% to 45%
Dec	1	15	7%	1% to 30%

Peak flowering in Apr. Each bar is the share of Viola sempervirens 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. 344 of 393 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 Viola sempervirens 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

Viola sempervirens

Redwood Violet

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.