When does Catclaw Acacia bloom in Arizona?

Most often in April. Across 143 dated, research-grade observations of Senegalia greggii in Arizona, the flowering season runs roughly April to June.

Peak April In flower 143 Examined 293 State Arizona

Flowering 143 in flower of 293 examined

Proportion of examined Senegalia greggii in Arizona in flower, by month
Month In flower Examined Share 95% interval
Jan 1 5 20% 4% to 62%
Feb 1 6 17% 3% to 56%
Mar 9 16 56% 33% to 77%
Apr 46 65 71% 59% to 80%
May 49 78 63% 52% to 73%
Jun 19 33 58% 41% to 73%
Jul 0 19 0% 0% to 17%
Aug 1 11 9% 2% to 38%
Sep 2 9 22% 6% to 55%
Oct 3 14 21% 8% to 48%
Nov 5 18 28% 13% to 51%
Dec 7 19 37% 19% to 59%

Peak flowering in Apr. Each bar is the share of Senegalia greggii in Arizona 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. 143 of 293 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 Arizona found Senegalia greggii in flower, not a forecast. It is computed only from observations made in Arizona, 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 Arizona. 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.