Great masterwort

Masterwort is a fully hardy perennial and comes through the Central European lowland winter in the bed without protection; in autumn you can cut the stems back close to the ground. Only in a container does it need protection: move the pot against the house wall, stand it on a wooden base and wrap it in horticultural fleece, because the roots are exposed to frost on all sides there.

The most reliable way to propagate masterwort is by division. It is also the only method that keeps cultivars true to type, and for many named cultivars it is the only option anyway (for example ‘Roma’ is sterile and sets no viable seed, so it can only be divided). It is best to divide established clumps in early spring as growth begins: water the plant well beforehand, dig out the whole root ball and split it with a sharp spade into several pieces, each with strong roots and shoots. The fine roots dry out quickly in the air, so replant the pieces promptly, about 30 to 45 cm apart, and water in well. You can set larger pieces straight into their new place; grow smaller ones on in pots until they are sturdy. Sowing is mainly suitable for the wild form, Astrantia major. Note: not all cultivars set viable seed, and seed you collect yourself from cultivars usually departs from the parent (different colour, different habit). For true-to-type plants, always choose division. The seeds are cold-stratification seeds and need a cold period of several weeks: sow fresh seed from autumn to winter directly outdoors or in pots that you leave outside over winter; a covering of snow helps germination. Alternatively, you can sow from February in a cold greenhouse or cold frame. The young plants germinate from spring and then need another 1 to 2 years until their first flowers.