Scotty's Fall Perennial To-Do List

Robert Scott spoke to our seminar attendees the other day about perennials and tasks that should be performed this time of year. Scotty has worked for over 20 years buying, selling and providing information about plants that come back every year. Here are his notes from Saturday's presentation.

Fall is a great time to plant perennials. The cool air temperatures and warm soil temperatures allow roots to expand even as the plants' foliage and flowers slow down.

Dead Heading (insert Jerry Garcia reference here) is important to keep flowers blooming into fall. Removing spent blossoms encourages additional late blooms on the following perennials:
Coreopsis
Echinacea
Rudbeckia
Heliopsis
Agastache

Many daisy-shaped flowers benefit from deadheading

Plant these perennials for fall color.
In Full Sun
Echinacea
Aster
Tall Sedums
Chrysnathemum nipponicum (Montauk Daisy)
Heliopsis (false sunflower)
Rudbeckia fulgida
Solidago
Ornamental grasses--Many colors and sizes look their best this time of year

Rudbeckia

Solidago (Goldenrod) and ornamental grasses provide color and interest well into fall

In Part Shade
Geranium Rozanne
Japanese Anemones
Chelone (turtlehead)
Begonia grandis
Tricyrtis (toad lily)

Planting tips
Use Espoma Bio-tone to establish plants faster
Use Leafgro compost to mix into soil (3 parts soil to 1 part Leafgro)
Dig holes 2-3 times as wide as root ball but only as deep as the rootball is tall

Care following a heavy frost or freeze
Scotty's Hamlet voice "To cut back or not cut back, that is the question"
Herbaceous perennials will likely die-back on their own, Try to leave 4-6" of the main foliage stem visible (Coreopsis, Astilbe, most Ferns etc.)

Tickseed Coreopsis will die back on their own. Deadhead them often for extended bloom time

Woody perennials may be deadheaded or leave the seed heads for winter food for finches and other birds. Cut-back in spring after new foliage disappears. (Perovskia, Lavender, Eupatorium, Caryopteris, Veronica etc.)

Eupatorium or Joe Pye Weed provides late summer and fall color. Butterflies love them. 

Leave these perennials intact for winter interest including seed heads.
Aster
Rudbeckia
Echinacea
Taller Sedums
Heliopsis
Helenium
Helianthus
Ornamental grasses

Perennial seedheads provide winter interest and food for the birds

Winter mulching
After a heavy frost, as soil temperatures cool, apply 1-2 inches of shredded hardwood mulch or compost around the perennials. Avoid putting too much over the base/crown of each plant; use barely enough to cover the ground. Mulch provides several benefits. It insulates the soil providing protection to the plants from freezing. Mulch also keeps soil temperatures more uniform, preventing plant heaving from occurring during extreme changing in soil temperatures. Mulch will also maintain some soil moisture.

Diseased leaves
As gardeners trim back foliage, be aware of any diseases that may be present. Discard leaves that may harbor fungi like powdery mildew, botrytis, or other leaf diseases often present on plants like Phlox, Monarda or Peonies. Dispose of all infected leaves; do not add them to the compost pile.

Pat cuts back perennials in our butterfly garden

Thanks again to Scotty for sharing this information. Please feel free to contact him on the phone at 410-527-0700.