Pods are yellow-grayish-brown, with straight lines, necklace-shaped, short and closely hirsute, easy shattered, with 5–6 seeds.
Researchers found that the seeds of L. perennis require scarification to germinate and ideal temperatures range from 24–29 °C (75–84 °F).
[5] It is widespread in the eastern part of the USA (from Texas and Florida to Maine) and Minnesota, Canada (southern Ontario, Newfoundland and Labrador), and on the coasts of the Arctic Ocean, where it grows in sandy areas such as dunes and savannas.
[11] Leaves that have been fed on by Karner blues have distinctive transparent areas where the larvae have selectively eaten only the green, fleshy parts.
Currently it is considered "rare" in Pennsylvania, a species of special concern in Rhode Island, threatened in Iowa, Maryland, and New Hampshire;[2] it is endangered in Vermont, and is extirpated from Maine.
[13] One reason this occurs is that lupine seed coats are so tough that only pressure changes due to rapid heating or abrasion are strong enough to allow water to penetrate and start germination.
[citation needed] Impacts of primary habitat loss have led to decreasing populations which are small and scattered which makes it harder for pollination to occur.