prairie spiderwort

not listed

N5? - Secure

SNR - Unranked

not listed

UPL - Obligate upland

UPL - Obligate upland

UPL - Obligate upland

Prairie spiderwort is a 16″ to 40″ tall, erect, perennial forb that rises on 1 to many stems from thick, fleshy, fibrous roots.

The stems are erect or ascending, often branched, usually hairless, green, and covered with a whitish, waxy or powdery film (glaucous). There are 2 to 6 nodes on the stem and up to 10″ between nodes.

The leaves are alternate, linear, 3½″ to 12″ long, and 1 ⁄16″ to ½″ wide but usually less than ⅜″ wide. They are hairless, bright green, glaucous, and rolled inward, not keeled. The upper leaves are as narrow or narrower than the part of the leaf that surrounds the stem when it is opened and flattened. The base of the leaf sheaths the stem. The tip tapers to a point with concave sides along the tip. The margins are untoothed and rolled inward toward the upper side.

The inflorescence is a tight, umbrella-like cluster of up to 25 flowers arising from the same point. They appear at the end of the stem, at the ends of branches, and often on long stalks rising from the leaf axils. A pair of bracts below the inflorescence are similar to the leaves and about the same size, 2″ to 8″ long.

The flowers are 1″ to 1½″ wide. They are on ⅓″ to 1⅛″ long stalks which droop when in bud, becoming erect when the flower opens. The flower stalks and sepals are sparsely hairy with minute, glandular hairs, the hairs no more than 1 ⁄64″ (0.5 mm) long. The sepals may have a tuft of hairs at the tip. The 3 petals are bright blue to rose or magenta and broadly egg-shaped. There are 6 stamens with bright yellow anthers. The petals last only one day, opening in the morning then turning to jelly in the mid-day heat. The central flowers bloom first. There is no floral scent.

The fruit is a papery, nearly round to oblong capsule ¼″ or less in diameter with 2 to 6 seeds.

8″ to 24″

Bright blue to rose or magenta

Bracted spiderwort (Tradescantia bracteata) stems are usually unbranched and bright green. The leaves are bright green and keeled, not rolled inward. Neither the stems nor the leaves are glaucous. The bracts are 2″ to 12″ long, often longer and wider than the leaves. The sepals and flower stalks are densely hairy with both long and short hairs.

Ohio spiderwort (Tradescantia ohiensis) is a taller plant, 16″ to 40″ tall at maturity. The stems are glaucous. The leaves are glaucous and flat, not rolled inward. The bracts are 2″ to 8″ long and no wider than the leaves. The sepals and flower stalks are usually hairless.

Dry or moderate moisture. Prairies, meadows, roadsides. Full sun.

June to July

Sources

2, 3, 4, 5, 7, 24, 28, 29, 30.

Native

Prairie spiderwort at Lebanon Hills Regional Park. Prolific along the road leading in to the Visitors Center.

Prairie spiderwort at Crosby Farm Regional Park

Flower

Plant and flower

Plant

Inflorescence

Flower

Leaves

Sepals

Buds

Location: Detroit Lakes, MN

volunteer growing in our flowerbed

Location: Lebanon Hills Regional Park

Prolific along the road leading in to the Visitors Center

Location: Crosby Farm Regional Park

Location: Joy Park & Preserve in Maplewood, MN

Location: Crosby Farm Regional Park, St.Paul, Ramsey County