Pickerel weed (Pontederia cordata) is an aquatic perennial plant recognized for its striking blue-purple flower spikes and glossy, heart-shaped leaves. It is a favored choice for aquatic gardens and plays a role in natural wetland ecosystems. While it can spread through rhizomes, propagating pickerel weed from seeds is a common and effective method to cultivate new plants.
Understanding Pickerel Weed Seeds
Pickerel weed seeds develop after the plant’s showy flower spikes have bloomed. These seeds are typically oblong and encased in a corky fruit or husk. They are released as the flower stem droops, allowing the seeds to fall into the water or muddy soil below.
Collecting Pickerel Weed Seeds
Collecting pickerel weed seeds is best done in late summer to early fall, after the plant has finished flowering. A key indicator of maturity is when the flower stem droops, and the seeds can be easily detached from the head. To harvest, gently pull or rub your hand across the mature seed head, allowing the seeds to fall into a container. If the seeds resist coming off, they are not yet fully ripe and should be left to mature further on the plant.
Preparing Pickerel Weed Seeds for Planting
Pickerel weed seeds often require a period of cold, moist stratification to break dormancy and encourage germination. This process mimics the natural winter conditions the seeds would experience. One method involves placing the cleaned seeds in damp sand or peat moss and refrigerating them at temperatures between 33-38°F (0.5-3.3°C). For short-term storage before stratification, dried seeds can be kept at room temperature for up to six months while maintaining viability.
Planting Pickerel Weed Seeds
Once stratified, pickerel weed seeds are ready for planting, ideally in spring. They germinate best in shallow water or consistently moist soil. A suitable growing medium includes heavy loam or an aquatic potting mix. For optimal germination, place the seeds in a container with the soil level just above the water line, or in water up to 12 inches deep. Maintaining water temperatures around 78-80°F (25-27°C) and ensuring about 12 hours of light can further support germination.
Caring for Young Pickerel Weed Plants
After germination, young pickerel weed plants need consistent moisture and ample sunlight to thrive. They prefer full sun exposure but can tolerate partial shade. Maintaining appropriate water levels is important; they generally prefer 3 to 5 inches of water, but can grow in up to 12 inches deep. Once seedlings are robust enough, they can be transplanted to their permanent location, such as along pond edges or in larger containers. When transplanting, ensure the root ball is planted at the same depth it was previously, and water immediately to help settle the soil.