When does red deadnettle bloom in Maryland?

Most often in April. Across 523 dated, research-grade observations of Lamium purpureum in Maryland, the flowering season runs roughly February to May.

Peak April In flower 523 Examined 561 State Maryland

Flowering 523 in flower of 561 examined

Proportion of examined Lamium purpureum in Maryland in flower, by month
Month In flower Examined Share 95% interval
Jan 16 22 73% 52% to 87%
Feb 17 22 77% 57% to 90%
Mar 156 163 96% 91% to 98%
Apr 301 313 96% 93% to 98%
May 25 26 96% 81% to 99%
Jun 1 1 too few examined
Jul 0 0 too few examined
Aug 0 0 too few examined
Sep 1 1 too few examined
Oct 2 3 too few examined
Nov 1 2 too few examined
Dec 3 8 38% 14% to 69%

Peak flowering in Apr. Each bar is the share of Lamium purpureum 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. 523 of 561 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 Lamium purpureum 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

Sourcesevery claim on this page

  1. 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.
  2. World Flora Online Plant List. The accepted name. CC0. Retrieved 2026-07-12.