Integrated Pest Management

Purple Deadnettle

Lamium purpureum

Purple Deadnettle

Purple deadnettle foliage (Ansel Oommen, Bugwood.org)

Purple Deadnettle

Purple deadnettle growth habit (Robert Videki, Bugwood.org)

Purple Deadnettle

Purple deadnettle seedlings (Bruce Ackley, The Ohio State University, Bugwood.org)

Description

  • produces square-shaped stems that grow 4 – 16 inches tall; stems are branched at the base and purplish in color
  • leaves are hairy, arrow shaped and oppositely arranged on stems; leaves have prominent veins that are recessed on blades and leaf margins are toothed
  • leaves are clustered around stem tips and the uppermost leaves are smaller and reddish purple in color, giving the plant the appearance of vertically standing hooded figures
  • flowers are small, purple and circle upper leaf axils; if studied carefully, flowers resemble tiny orchid blooms with a white face and purple spots

Location

  • commonly grows in planting beds and lawn areas

Life Cycle

  • a winter annual with seeds that germinate in the fall although a lesser portion of seeds may also germinate in the spring
  • seedlings do not germinate during hot summer temperatures; purple deadnettle plants complete their life cycle before hot temperatures set in and seeds can germinate immediately as long as temperatures are not too high

IPM Recommendations

  • Hand-pull plants in planting beds prior to seed maturation.
  • Apply an appropriate pre-emergent herbicide prior to seed germination or apply an appropriate post-emergent herbicide directly to target weeds.