There are certain perennials which require special attention for their best development. The perennials in this group should be taken up, divided, and replanted every two or three years, as they grow more vigorously and multiply faster than the other groups of perennials.

a. To be divided every two years:

Anemone japonica

Japanese Windflower Aquilegia

Columbine Chrysanthemum (hardy, large-flowered varieties)

Hardy Chrysanthemum Helianthemum croceum

Rock Rose Helianthus

Hardy Sun-flower

Lychnis coronaria Mullein Pink

Monarda didyma Bergamot

Paeonia (in variety)

Peony (only to multiply)

Phlox paniculata Garden Phlox

Rudbeckia Cone-flower b. To be divided every three years:

Armeria (in variety) Sea Thrift

Iris (all varieties) Iris

Phlox paniculata Garden Phlox

Thymus serpyllum lanuginosus Downy Thyme

Viola (in variety) Violet c. To be divided each year:

Anthemis tinctoria kelzoayi

Hardy Marguerite Aster novae-angliae (in variety)

Hardy Garden Aster

Aster novi-belgi (in variety) Hardy Garden Aster

Bellis perennis English Daisy

Bocconia cordata Plume Poppy

Chrysanthemum indicum Pompom Chrysanthemum

Chrysanthemum maximum Shasta Daisy

Helenium (in variety) Sneezeweed