When does Pulsatilla nuttalliana bloom in Minnesota?

Most often in April. Across 248 dated, research-grade observations of Pulsatilla nuttalliana in Minnesota, the flowering season runs roughly March to April.

Peak April In flower 248 Examined 320 State Minnesota

Flowering 248 in flower of 320 examined

Proportion of examined Pulsatilla nuttalliana in Minnesota in flower, by month
Month In flower Examined Share 95% interval
Jan 0 0 too few examined
Feb 1 1 too few examined
Mar 53 61 87% 76% to 93%
Apr 151 167 90% 85% to 94%
May 36 60 60% 47% to 71%
Jun 5 11 45% 21% to 72%
Jul 1 10 10% 2% to 40%
Aug 0 7 0% 0% to 35%
Sep 1 2 too few examined
Oct 0 0 too few examined
Nov 0 1 too few examined
Dec 0 0 too few examined

Peak flowering in Apr. Each bar is the share of Pulsatilla nuttalliana in Minnesota 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. 248 of 320 examined observations were in flower, every one of them research grade. The whisker on each bar is a 95% Wilson interval. 6 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 Minnesota found Pulsatilla nuttalliana in flower, not a forecast. It is computed only from observations made in Minnesota, 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 Minnesota. 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.