This tall plant has tuberous or thickened roots and all parts are poisonous. Monkshood needs well-drained, moist soil and partial shade. The plant grows best in cool weather and is not harmed by light frosts in the fall. Monkshood does not like to be disturbed.
Propagation is by seed, or division done in autumn or early spring.
Delay division until the plants absolutely need it. Starting seed may not be reliable. The seed needs moist storage at 41 degrees for six weeks to overcome dormancy. This information is for educational purposes only. References to commercial products or trade names does not imply endorsement by MSU Extension or bias against those not mentioned.