What's eating my sanguisorba 'tanna'?

Sanguisorba 'Tanna', a compact dwarf burnet, shares the genus's generally excellent pest resistance. Deer and rabbits are the worst real-world threat. Vine weevil is a risk in containers. Slugs may nibble newly emerging foliage. Once established in open ground, 'Tanna' is among the most reliable and low-fuss perennials available.

Foliage grazed down, particularly damaging to this compact cultivar where loss of leaves removes most of the ornamental value. Wire or mesh guards are most reliable. Deer repellent sprays applied regularly. Plant in a walled or fenced garden where possible.

Root-feeding grubs cause sudden wilting and plant death in pots; adults leave characteristic D-shaped notches on leaf edges. Use nematode (Steinernema kraussei) compost drenches in late summer or autumn. Inspect container root balls annually. Avoid overwatering, which favours grub survival.

Small holes in soft spring foliage; low-level damage unlikely to threaten a healthy established plant. Ferric phosphate pellets around the crown at bud-break. Sharp grit mulch deters slugs while improving drainage.