When does common jewelweed bloom in Maryland?

Most often in August. Across 285 dated, research-grade observations of Impatiens capensis in Maryland, the flowering season runs roughly June to October.

Peak August In flower 285 Examined 300 State Maryland

Flowering 285 in flower of 300 examined

93%

95%

100%

85%

Proportion of examined Impatiens capensis in Maryland in flower, by month
Month	In flower	Examined	Share	95% interval
Jan	1	1	too few examined
Feb	0	0	too few examined
Mar	0	0	too few examined
Apr	0	5	0%	0% to 43%
May	0	3	too few examined
Jun	27	29	93%	78% to 98%
Jul	35	37	95%	82% to 99%
Aug	82	82	100%	96% to 100%
Sep	121	121	100%	97% to 100%
Oct	17	20	85%	64% to 95%
Nov	2	2	too few examined
Dec	0	0	too few examined

Peak flowering in Aug. Each bar is the share of Impatiens capensis in Maryland 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. 285 of 300 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 Maryland found Impatiens capensis in flower, not a forecast. It is computed only from observations made in Maryland, 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

Impatiens capensis

common jewelweed

Sourcesevery claim on this page

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