When does yellow nightshade groundcherry bloom in California?

Most often in March. Across 2,234 dated, research-grade observations of Physalis crassifolia in California, the flowering season runs roughly January to December.

Peak March In flower 2,234 Examined 2,659 State California

Flowering 2,234 in flower of 2,659 examined

82%

87%

90%

81%

71%

64%

40%

83%

84%

89%

83%

78%

Proportion of examined Physalis crassifolia in California in flower, by month
Month	In flower	Examined	Share	95% interval
Jan	372	456	82%	78% to 85%
Feb	457	524	87%	84% to 90%
Mar	505	561	90%	87% to 92%
Apr	169	208	81%	75% to 86%
May	52	73	71%	60% to 80%
Jun	7	11	64%	35% to 85%
Jul	2	5	40%	12% to 77%
Aug	10	12	83%	55% to 95%
Sep	36	43	84%	70% to 92%
Oct	121	136	89%	83% to 93%
Nov	220	266	83%	78% to 87%
Dec	283	364	78%	73% to 82%

Peak flowering in Mar. Each bar is the share of Physalis crassifolia 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. 2,234 of 2,659 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 Physalis crassifolia 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

Physalis crassifolia

yellow nightshade groundcherry

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.