When does fairyduster bloom in Arizona?

Most often in March. Across 384 dated, research-grade observations of Calliandra eriophylla in Arizona, the flowering season runs roughly March to November.

Peak March In flower 384 Examined 490 State Arizona

Flowering 384 in flower of 490 examined

58%

73%

91%

84%

73%

17%

33%

11%

64%

83%

68%

Proportion of examined Calliandra eriophylla in Arizona in flower, by month
Month	In flower	Examined	Share	95% interval
Jan	18	31	58%	41% to 74%
Feb	37	51	73%	59% to 83%
Mar	167	183	91%	86% to 95%
Apr	92	109	84%	76% to 90%
May	19	26	73%	54% to 86%
Jun	1	6	17%	3% to 56%
Jul	0	3	too few examined
Aug	3	9	33%	12% to 65%
Sep	1	9	11%	2% to 44%
Oct	7	11	64%	35% to 85%
Nov	20	24	83%	64% to 93%
Dec	19	28	68%	49% to 82%

Peak flowering in Mar. Each bar is the share of Calliandra eriophylla 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. 384 of 490 examined observations were in flower, every one of them research grade. The whisker on each bar is a 95% Wilson interval. One month has fewer than 5 examined observations, so no proportion is drawn for it. 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 Calliandra eriophylla 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

Calliandra eriophylla

fairyduster

Sourcesevery claim on this page

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