The Well-Tended Perennial Garden The Essential Guide to Planting and Pruning Techniques, Third Edition

12. erennials that may require division every P
    6–10 years

Alchemilla mollis

Amsonia*

Arum italicum

‘Pictum’

Asarum europaeum

Begonia grandis

Brunnera

macrophylla

Echinacea purpurea

Echinops ritro*†

Epimedium*

Ferns, most

Filipendula rubra

‘Venusta’†

Filipendula ulmaria

Gaura lindheimeri

Gentiana septemfida

var. lagodechiana

Geranium

Iberis sempervirens*

Iris sibirica

Kniphofia hybrids

Ligularia dentata

Limonium

platyphyllum*

Nepeta

Ornamental grasses,

most

Papaver orientale*

Patrinia scabiosifolia

Phlomis

Polygonatum

odoratum

‘Variegatum’

Pulmonaria

Rodgersia

Ruta graveolens

Salvia ×sylvestris

Sedum ‘Matrona’

Spigelia marilandica

Symphytum

×uplandicum

‘Axminster Gold’

Telekia speciosa

Thalictrum

aquilegiifolium

Tricyrtis hirta

Trollius ×cultorum*

Verbascum

*resents disturbance

†tough woody or thonglike roots or taproot

Iris sibirica