When does Jack in the bush bloom in Texas?

Most often in June. Across 661 dated, research-grade observations of Chromolaena odorata in Texas, the flowering season runs roughly January to December.

Peak June In flower 661 Examined 733 State Texas

Flowering 661 in flower of 733 examined

83%

81%

91%

93%

97%

100%

83%

89%

93%

89%

Proportion of examined Chromolaena odorata in Texas in flower, by month
Month	In flower	Examined	Share	95% interval
Jan	43	52	83%	70% to 91%
Feb	30	37	81%	66% to 91%
Mar	20	22	91%	72% to 97%
Apr	66	71	93%	85% to 97%
May	38	39	97%	87% to 100%
Jun	8	8	100%	68% to 100%
Jul	1	2	too few examined
Aug	1	1	too few examined
Sep	20	24	83%	64% to 93%
Oct	161	180	89%	84% to 93%
Nov	206	222	93%	89% to 96%
Dec	67	75	89%	80% to 95%

Peak flowering in Jun. Each bar is the share of Chromolaena odorata in Texas 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. 661 of 733 examined observations were in flower, every one of them research grade. The whisker on each bar is a 95% Wilson interval. 2 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 Texas found Chromolaena odorata in flower, not a forecast. It is computed only from observations made in Texas, 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

Chromolaena odorata

Jack in the bush

Sourcesevery claim on this page

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