Winterkill occurs when several consecutive nights are in the low 20s. Leave plants in the ground all winter and into spring: roots decompose leaving large holes that fill with rainwater, eliminating runoff and improving soil drainage. Decomposed root and leaf matter release nutrients and increase microbial activity in the soil, contributing to increased yields in crops that follow. Mainers should plant in late August or early September for maximum benefit. Can be planted as late as October in mid-Atlantic states. Do not plant in spring: the plants will bolt before they form taproots. Drill at 5–10#/acre or broadcast at 10–15#/acre, ½# per 1000 sq ft. ② Note: We cannot ship this to Oregon’s Willamette Valley.