Reading Rob's comment about Melianthus major smelling of peanut butter has got me…
They will produce marginally frost hardy to frost tender plants, they will require full sun or light shade with fertile, moist but well-drained soil. You can propagate from seed in the early spring. They are poisonous and allergenic.
Annual sow then plant out
Pests, diseases or disorders
Watch for snails and caterpillars.