Lonicera dioica

Native

Common but not abundant

Moist. Forest edges and clearings, thickets, lakeshores, river banks. Partial or full sun.

Mid-May to early June

Purplish

3′ to 9′ long

This is a perennial vine or semi-erect shrub. It usually climbs over adjacent vegetation or sprawls on the ground. Occasionally, it forms a mound of arching stems.

The stems are climbing, sprawling, or semi-erect and arching. They are round, up to ¾″ in diameter, and can be 3′ to 9′ long but are usually 5′ to 6½′ long. First-year branches are greenish, hairless, and usually covered with a whitish, waxy bloom (glaucous). Second-year branches are gray or brown. The bark of mature stems is gray or brown with long, fibrous, shredded, peeling strips. The buds are egg-shaped and pointed. The leaf scars are thin and crescent-shaped with 3 vascular bundle scars.

The leaves are opposite and variable in shape; oblong, elliptic, or inversely egg-shaped. The larger leaves are 2″ to 3½″ long, and 1¼″ to 2¾″ wide. They are rounded or blunt at the tip and tapered or rounded at the base. They may be stalkless or on leaf stalks up to ⅜″ long. The upper surface of the leaf blade is dark green and hairless. The lower surface is bluish or whitish, glaucous, and is usually moderately to densely hairy, occasionally hairless. The margins are untoothed, often wavy, and do not have a fringe of long hairs.

On flowering stems the uppermost pair of leaves is fused together at the base into a single disk-like leaf. The tip of each fused leaf is tapered to a point or is rounded and has a tiny, short, sharp, abrupt point. The upper surface is green and is not glaucous.

The inflorescence is 1 to 3 whorls of 6 stalkless flowers per whorl on a single spike (rarely 3 spikes) at the end of the stem. The whorls are not separated and the flowers are crowded.

The flowers are ⅝″ to 1″ long and are strongly symmetrical, so that a plane dividing the flower in two would produce one side that is a mirror image of the other. There are 5 petals fused at the base into a corolla tube then separated ⅓ to ½ of the way to the base into 2 lips. The upper lip is divided into 4 shallow lobes, the lower lip is undivided. The petals are purple, red, or, rarely, yellow tinged with purple or red. There are 5 stamens with yellow anthers and a style with a light green, head-like stigma. The stamens and style protrude well beyond the corolla tube. The flowers appear on last season’s stems after the leaves are fully developed and peak from mid-May to early June. In Minnesota they are pollinated by ruby-throated hummingbird (Archilochus colubris) and bumblebees (Bombus sp.).

The fruit is a soft, globular, 5 ⁄16″ to ½″ in diameter berry. It is green initially, becoming orange, ultimately red or orange-red when ripe. They do not fall but remain on the plant until picked off by birds or they dry on the plant. It matures in late June to early August.

Grape honeysuckle (Lonicera reticulata) leaves are nearly circular. The upper 2 or 3 pairs of leaves are fused at the base into single disk-like leaves. The upper surface of the fused leaves is often glaucous and bluish. The flower whorls are normally separated from one another. The flowers are pale yellow. In Minnesota it is found only in the southeast.

Hairy honeysuckle (Lonicera hirsuta) leaves are narrowly elliptic. The upper leaf surface is velvety-hairy. The leaf margins have a fringe of long hairs. The flowers are yellow.