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Milkweed seed - Swamp : Tall variety best for attracting monarchs.
Milkweed seed - Swamp : Tall variety best for attracting monarchs.
Milkweed seed - Swamp : Tall variety best for attracting monarchs.

Milkweed - Swamp

Asclepias incarnata

Beautiful rose to lilac blooms on tall 35 - 50" plants set swamp milkweed apart. A good choice for the back of border plantings, or place it near streams or boggy areas, as this variety gets its name because it tolerates having wet feet. One of the best varieties for attracting Monarchs, but also just a great all around pollinator plant. Summer blooming. Full sun to part shade. Perennial. Approx. seeds per packet = 90 (1/2 Gram Packet)

Regular price $2.75 $2.75 Sale

Average Seed / oz Seed / 100' Row Average Yield / 100' Row Days to Harvest
4800 n/a n/a 70
Planting Season Ideal Soil Temp Sun Frost Tolerance
Fall 65-80°F Full Sun Lightly Tolerant
Sowing Method Seed Depth Direct Seed Spacing Seeds Per Packet
Direct Seed 1/8" 6-8" 90
Mature Spacing Days to Sprout Production Cycle Seed Viability
24-36" 21-28 Perennial 2-3 years

Site Selection

These North American native milkweeds are hardy perennials that will tolerate full sun to partial shade and thrive in a wide variety of soils. Swamp milkweed (A. incarnata), as the name suggests, prefers moist soils, but will tolerate average soils if not too dry.

Cultivation

For best results, expose seeds to moist, cold conditions (stratification) prior to sowing. For cold stratification, place seeds in moist potting soil or sand and store in a refrigerator for 4-6 weeks. After stratification, sow seeds in containers or direct seed outdoors after the danger of frost has passed. Sow seeds 1/8-1/4" deep and 6-8" apart. Optimal soil temperature for germination is 65-80˚F. Seeds will sprout in 10-28 days. Thin seedlings so that mature plants are 24-36" apart.

Seeds can also be direct sown outdoors in the fall where they will stratify naturally and germinate the following spring.