When does Common Cat's-ear bloom in Oregon?

Most often in June. Across 207 dated, research-grade observations of Hypochaeris radicata in Oregon, the flowering season runs roughly June to October.

Peak June In flower 207 Examined 333 State Oregon

Flowering 207 in flower of 333 examined

69%

94%

89%

92%

87%

88%

69%

17%

Proportion of examined Hypochaeris radicata in Oregon in flower, by month
Month	In flower	Examined	Share	95% interval
Jan	2	22	9%	3% to 28%
Feb	0	10	0%	0% to 28%
Mar	0	21	0%	0% to 15%
Apr	1	23	4%	1% to 21%
May	36	52	69%	56% to 80%
Jun	44	47	94%	83% to 98%
Jul	40	45	89%	77% to 95%
Aug	22	24	92%	74% to 98%
Sep	26	30	87%	70% to 95%
Oct	22	25	88%	70% to 96%
Nov	11	16	69%	44% to 86%
Dec	3	18	17%	6% to 39%

Peak flowering in Jun. Each bar is the share of Hypochaeris radicata in Oregon 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. 207 of 333 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 Oregon found Hypochaeris radicata in flower, not a forecast. It is computed only from observations made in Oregon, 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

Hypochaeris radicata

Common Cat's-ear

Sourcesevery claim on this page

GBIF (iNaturalist Research-grade Observations). Dated flowering annotations in Oregon. 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.