When does eastern poison ivy bloom in Texas?
Most often in April. Across 151 dated, research-grade observations of Toxicodendron radicans in Texas, the flowering season runs roughly April.
Flowering 151 in flower of 1,915 examined
Peak flowering in Apr. Each bar is the share of Toxicodendron radicans 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. 151 of 1,915 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 Texas found Toxicodendron radicans 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
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.