When does silverleaf nightshade bloom in Arizona?

Most often in May. Across 198 dated, research-grade observations of Solanum elaeagnifolium in Arizona, the flowering season runs roughly May to August.

Peak May In flower 198 Examined 560 State Arizona

Flowering 198 in flower of 560 examined

25%

83%

82%

48%

70%

56%

Proportion of examined Solanum elaeagnifolium in Arizona in flower, by month
Month	In flower	Examined	Share	95% interval
Jan	0	23	0%	0% to 14%
Feb	0	32	0%	0% to 11%
Mar	0	40	0%	0% to 9%
Apr	18	72	25%	16% to 36%
May	45	54	83%	71% to 91%
Jun	40	49	82%	69% to 90%
Jul	15	31	48%	32% to 65%
Aug	53	76	70%	59% to 79%
Sep	22	39	56%	41% to 71%
Oct	4	62	6%	3% to 15%
Nov	1	41	2%	0% to 13%
Dec	0	41	0%	0% to 9%

Peak flowering in May. Each bar is the share of Solanum elaeagnifolium 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. 198 of 560 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 Solanum elaeagnifolium 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

Solanum elaeagnifolium

silverleaf nightshade

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.