Our Culvers Root has grown to about 5ft high and bloomed. To strengthen the plant for next year should we now cut off the top/head or should we leave it alone to die in due course and might the seeds propagate for next year?
What a wonderful choice for your garden. Not only is it beneficial for pollinators, but aesthetically Culver’s root is such an elegant native perennial plant with its candelabrum-like spikes. As the flowers fade, you can deadhead the spikes to encourage more flowering and extend the bloom period. Once flowering is complete, cutting the plant back in early summer stimulates growth, producing abundant basal leaves and a potential second bloom in late summer or fall.
In the autumn, the main objective of pruning perennials is to minimize pest and disease problems. Culver’s root is not subject to serious insect or disease problems, and the stems and plant litter can provide a home for overwintering insects. The choice is yours to make, but Mark Cullen’s Perennials: Some you cut down, some you leave standing has helpful information – including “If it is ugly and you don’t like the look of it – cut it back”.
Culver’s root can be difficult to grow from seed. The seed, which is held in small woody capsules, that do not fall easily. The capsule must be slightly crushed for the seed to be released. It is much easier to propagate by dividing the plant in late fall or early spring. Just make sure each root stock has a bud to be successful.
Septemer 4, 2021