Longleaf Ground Cherry is a perennial forb growing 1 to 3 feet high on stems where the upper part is usually without hair. Stems are purple-green, have 4+ ridges and branch frequently, creating a bushy effect and are erect initially but when later in fruit may be decumbent.
The leaves are narrowly lance-like, tapering at both ends, with a rounded tip and a base that is usually not symmetrical, leading to a stalk. The margins have irregular wavy teeth or may be entire. The surfaces may have coarse hair or may be mostly smooth. Two varieties are currently accepted but the main difference seems to be in the narrowness of the leaf and the amount of teeth, so we will not distinguish them here other to list them as var. longifolia and var. subglabrata.
The inflorescence consists of solitary stalked pendant flowers that rise from the leaf axils.
Flowers: The flower stalk usually has fine hair while the calyx may have only sparse hair on the main 5 triangular lobes. The corolla is funnel shaped, yellow with 5 shallow lobes which overlap with little separation visible at the lobe tips. Inside the corolla there is a brownish to purplish spotted area in the center of each lobe. The five stamens have purple filaments with yellow anthers which form around the central ovary. There is a single style.
Seed: Fertile flowers form an inflated husk from the calyx, slightly longer than wide, that contains a single 1/3 to 1/2 inch diameter round berry, green initially, turning orange at maturity and containing a number of seeds. The husk is mostly closed at the tip and turns brown at maturity.
Invasive: The root system can create vast colonies of plants.
Habitat: Longleaf Ground Cherry grows in dry areas, prairies, woods, in rich to disturbed soils. Full sun to partial sun with moderate moisture. The plants have flowers, buds forming, husks and maturing berries all at the same time. It grows from a rhizomatous root system and can spread vegetatively to form colonies.
Names: The genus Physalis is derived from the Greek word physa, meaning 'a bladder' and referring to the inflated calyx at seed time. The species longifolia refers to the longer more narrow leaf. The author name for the plant classification - ‘Nutt.’ is for Thomas Nuttall (1786-1859) English botanist who lived and worked in America from 1808 to 1841. On his many expeditions he collected many species that had been originally collected by Lewis and Clark but lost by them on their return journey. He also collaborated with French botanist Francois Andre Michaux (1770-1855) in Michaux’s 3 volume North American Sylva.
Comparisons: While this species is not known to be frequently found in Minnesota there are two others native here that are only slightly different. P. heterophylla the Clammy Ground Cherry, has more broadly ovate leaves that are densely hairy. P. virginiana, the Virginia Ground Cherry has lance-like leaves and less hair than the former. Both plants are shorter and do not form colonies.
Above: 1st photo - Calyx, stem and outer corolla may have sparse fine hair. 2nd photo - The stamens have purple filaments with yellow anthers and in this developing flower, are forming around the central ovary.
Below: The flower calyx inflates at maturity into a ribbed green husk, closed at the tip. It matures to a brown color. These arise from the leaf axils.
Below: The ribs of the husk show the sparse hair found on it and on the calyx.
Below: The leaves are narrowly lance-like, unsymmetrical, with irregular wavy teeth, or may be entire. Surfaces may be smooth to coarsely hairy.
Below: 1st photo - The underside of this leaf is smooth except for some fine hair on the veins. 2nd photo - The stems have 4+ ridges, branch frequently, and may be smooth to having rough hair. 3rd photo - Young seed pods.
Below: Inside the inflated husk a 1/2 inch diameter green berry develops that turns to orange at maturity.
Below: The rhizomatous root system can form dense colonies as seen here making the plant an invasive pest.
Notes: Longleaf Ground Cherry is not known to have ever been in the Eloise Butler Wildflower Garden.
The MN DNR lists two species of Physalis native and found in Minnesota: P heterophylla var heterophylla, Clammy Ground Cherry; and P. virginiana, the Virginia Ground Cherry. They are rather widespread. The University of Minnesota Herbarium also reports other species that have been reported but without specimens ever collected. The photos shown here were taken of a large group of plants on the right of way of the Xcel Energy hi-voltage powerline in Minnetonka. The species from the Nightshade family in Minnesota that are found in the Garden are - Black Nightshade, Climbing Nightshade and Clammy Ground Cherry.
The Genus Physalis: An alternate name for these species is "husk-tomato" - the small fruit resembles a tomato and is said to taste like one, although strongly, and it ripens within the inflated calyx - thus a "husk". Some species are annuals and some grow from rhizomatous roots and are perennial. They are widespread. As members of the Nightshade family, they have been sought out for medicinal purposes. Our species, P. longifolia, the Long-leaved Ground Cherry, is of particular interest in cancer research. This article from the University of Kansas explains that. Domesticated tomatillos have long been used as foodstuff by Native American peoples. Harrington (Ref. #9) and others report that most fecal samples from archaeological sites in the southwest contain seeds of the species.
References: Plant characteristics are generally from sources 1A, 32, W2, W3, W7 & W8 plus others as specifically applied. Distribution principally from W1, W2 and 28C. Planting history generally from 1, 4 & 4a. Other sources by specific reference. See Reference List for details.
Identification booklet for most of the flowering forbs and small flowering shrubs of the Eloise Butler Wildflower Garden. Details Here.
Friends of the Wild Flower Garden, Inc. Text and photos are by G. D. Bebeau unless otherwise credited. "www.friendsofthewildflowergarden.org"