When does Pacific Bleeding Heart bloom in Oregon?

Most often in May. Across 1,295 dated, research-grade observations of Dicentra formosa in Oregon, the flowering season runs roughly April to June.

Peak May In flower 1,295 Examined 1,744 State Oregon

Flowering 1,295 in flower of 1,744 examined

Proportion of examined Dicentra formosa in Oregon in flower, by month
Month In flower Examined Share 95% interval
Jan 1 1 too few examined
Feb 0 17 0% 0% to 18%
Mar 26 153 17% 12% to 24%
Apr 463 552 84% 81% to 87%
May 417 480 87% 84% to 90%
Jun 178 211 84% 79% to 89%
Jul 103 153 67% 60% to 74%
Aug 75 117 64% 55% to 72%
Sep 21 39 54% 39% to 68%
Oct 9 17 53% 31% to 74%
Nov 2 4 too few examined
Dec 0 0 too few examined

Peak flowering in May. Each bar is the share of Dicentra formosa 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. 1,295 of 1,744 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 Oregon found Dicentra formosa 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

Sourcesevery claim on this page

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