When does Parry's jepsonia bloom in California?

Most often in September. Across 453 dated, research-grade observations of Jepsonia parryi in California, the flowering season runs roughly September to November.

Peak September In flower 453 Examined 821 State California

Flowering 453 in flower of 821 examined

Proportion of examined Jepsonia parryi in California in flower, by month
Month In flower Examined Share 95% interval
Jan 10 78 13% 7% to 22%
Feb 0 56 0% 0% to 6%
Mar 0 65 0% 0% to 6%
Apr 0 20 0% 0% to 16%
May 0 5 0% 0% to 43%
Jun 0 0 too few examined
Jul 0 0 too few examined
Aug 0 1 too few examined
Sep 12 12 100% 76% to 100%
Oct 145 146 99% 96% to 100%
Nov 170 172 99% 96% to 100%
Dec 116 266 44% 38% to 50%

Peak flowering in Sep. Each bar is the share of Jepsonia parryi 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. 453 of 821 examined observations were in flower, every one of them research grade. The whisker on each bar is a 95% Wilson interval. 3 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 Jepsonia parryi 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.