How to Propagate Geranium robustum?
Propagate by division or by seed in spring, or take basal cuttings in early to mid spring and root with bottom heat.

Geranium robustum · Geranium robustum
Grow in any moderately fertile soil apart from waterlogged soils. Full sun or partial shade is best for good growth and flowering
Propagate by division or by seed in spring, or take basal cuttings in early to mid spring and root with bottom heat.