Amorpha fruticosa, commonly called False Indigo or Indigobush, is a native deciduous legume shrub belonging to the Fabaceae family. This nitrogen-fixing plant features distinctive purple flowers and is highly valued for erosion control, wildlife habitat, and ornamental purposes across North America. Seed germination requires scarification to overcome the hard seed coat, but once properly treated, seeds germinate readily within 20-30 days at warm temperatures.
Before sowing
Seeds have a hard, water-impermeable seed coat. Without pretreatment, germination rates may be only 10% or less. Scarification is essential to break seed dormancy and improve germination success.
Sowing
What to expect
Tips
1. Sow seeds 1/16 inch (1.6 mm) deep, tamp the soil firmly, and lightly mulch the seed bed. 2. Fall sowing in mulched beds is preferred and may negate the need for scarification. 3. Seeds require warm temperatures (70°F/21°C or higher) to germinate; do not expose to cold. 4. Direct sowing is best as seedlings do not tolerate transplanting well. 5. Germination is rapid (7-10 days) once seeds have absorbed water and swollen. 6. Remove only swollen seeds after scarification; small seeds may germinate later and should be sown. 7. Keep substrate consistently moist but not waterlogged during germination period.
Sources: USDA Forest Service, UF/IFAS Landscape Plant Propagation, Lady Bird Johnson Wildflower Center, Tallgrass Prairie Center, Native Seed Network, Tree Seed Online, Plants for a Future, Springer Journal of Seed Biology
