Virginia Tech Weed Identification Guide

Maypop Passionflower: Passiflora incarnata

maypop8-7.jpg (77713 bytes) Weed Description:  A herbaceous perennial vine with distinctive 3-lobed leaves and attractive flowers that my reach 6 1/2 feet or more in length.  Maypop passionflower is primarily found along the edges of woods and fields, but is becoming more noticeable in many of Virginia's agronomic crops, especially where conservation tillage is practiced.  Maypop passionflower is found from southern Oklahoma east to Virginia, south to Florida and west to central Texas.
Seedlings:  Cotyledons are oval, thick, and have a waxy appearance.  The first true leaf is heart-shaped and also glossy.  Subsequent leaves have lobes (usually 3) arising from a common point (palmately lobed leaves).  Seedlings can occur but sprouts from the perennial rootstocks are much more common.
Roots: Roots initially develop as a taproot but eventually develop a very deep perennial rootstock from which sprouts can emerge.
Leaves:  Arranged alternately along the stem, usually only slightly hairy.  Individual leaves are divided into 3 (only sometimes 5) lobes that arise from a common point (palmately lobed).  Leaves are approximately 2 1/2 to 5 1/2 inches long and wide and occur on petioles.  A pair of nectar-filled glands occurs at the base of the leaf blade and the junction of the petiole.
Stems:  Stems can trail along the ground or climb on other vegetation.  Stems or usually only slightly hairy and may reach 6 1/2 feet in length.
Flowers: Solitary flowers arise from the area between stem and leaf petioles.  Flowers range from 2 to 4 inches in length and are very attractive and light purple to lavender in color.
Fruit: A relatively large (1 1/2 - 3 inches long) berry that is green or yellowish-green in color.  Stepping on these berries when mature often causes a loud 'popping' sound, thus the name of this plant.   Berries contain many dark brown 'dimpled' seed (reticulate seed).
Identifying Characteristics:  The 3-lobed leaves, vining habit, deep rootstock, and attractive flower are all characteristics that help to distinguish maypop passionflower from other weeds.