What weeds are most common in your garden? Lots of nettles? Then you have rich, damp soil. Field buttercup, Wood aven, mosses and sedges? Then you have wet…
Dead-head to prevent self-seeding. They are fully hardy and will tolerate sun or shade in any but wet soil.
You can propagate by division in the spring or by seed in the autumn.
Pests, diseases or disorders
Mildew may be a problem.