Ludwigia decurrens

Habitat:
Grows along wetland edges, marshes, ditches, wet meadows, and the margins of slow-moving streams. Prefers consistently moist soils with periodic shallow flooding. Classified as a Facultative Wetland species (FACW), which means it is usually found in wetlands but can also grow in moist upland areas within the coastal plain.

When to Collect:
Collect seeds in late summer to early fall once the narrow capsules along the stem turn brown and dry. Mature capsules split lengthwise, and the tiny seeds can be shaken out easily. Students look for capsules that feel crisp and rattle when tapped.

When to Plant:
Plant in late winter or early spring. The USDA profile indicates that seeds germinate easily and do not require cold stratification.

How to Plant:
Sow seeds on the surface of moist sandy or sandy-clay soil. Do not cover the seeds because light helps stimulate germination. Press gently into the soil surface and keep the substrate evenly moist. This species grows well in shallow nursery trays or small wetland test plots that stay damp.

Light Requirements:
Full sun to partial shade. Plants growing in full sun tend to grow taller and produce more flowers and seed capsules.

Soil Preference:
Moist, sandy, or sandy-clay soils with slight acidity. Tolerates seasonal flooding but prefers areas where the soil drains slowly and stays consistently damp.

Growth Notes:
A tall wetland wildflower that commonly grows three to six feet with bright yellow four-petaled blooms throughout summer. Winged stems help students recognize the species quickly. Provides nectar and structure for wetland insects and may form small colonies in damp soils.

Fun Fact:
Each capsule holds hundreds of tiny seeds that look like grains of sand. Students often describe the stems as having “little wings” that help the plant stand out from other wetland species.