Swamp Milkweed Seeds

Swamp Milkweed seeds require cold stratification, and if you skip this, forget decent germination. The easiest method for growing Swamp Milkweed is to direct sow the seeds in late fall, just below the surface of the soil, and let nature do the work. To direct sow in the spring, mix the seeds of Asclepias Incarnata with sand and cold stratify them for 30 days. If done properly, Swamp Milkweed flower seeds germinate in 7-28 days. Thin the seeds, but do not transplant, as the taproots don't like being disturbed.

Full sun to part sun is fine, but full sun will give you a stockier plant with more blooms. The key requirement for this plant is moisture. For Swamp Milkweed seeds, you need damp soil, rain gardens, low-lying beds, areas near a downspout. This plant does not tolerate drought as prairie Milkweed does. Dry soil will slow it down.

Space them 18-36 inches apart, as they slowly spread through rhizomes over several years. The weeds require the most attention in the first year, before the plant gets established. After that, it takes care of itself. Cut the plant for a fresh bouquet once the flowers open, as they will hold well in a vase. Allow some 3-4 inch Swamp Milkweed seed pods to mature in the fall, harvest them before they split, remove the floss, and store them in a cool, dry place for the following season.