What to plant in the fall

The seeds of a good garden
Fall sowing is a nearly forgotten art, but one worth exploring. In nature, seeds—be they from perennials, annuals, trees or shrubs—mostly fall to the ground in autumn to germinate the following spring (many hardy plants won't even sprout, or only poorly, without experiencing cold temperatures). So if you've been sowing hardy plants in spring with only marginal results, try planting seeds in fall instead. Even many annuals, such as sweet peas, mallow, spider flower, pansies, larkspur, ornamental cabbage and snapdragons, do best when sown in autumn, as will any plant listed as a “hardy annual” in the seed catalogues.

Sod it now
Lawns do much better started in fall. The cool air temperatures reduce evaporation and slow foliage growth, giving the roots time to dig in. Typically, lawns sown or sodded in fall grow just enough to look good, but really show their strength the following summer when, thanks to a deep, well-established root system, they breeze through summer droughts. Sod or sow lawns at least eight weeks before the first killing frost.

Wait for spring
Although you might see some tempting sale prices at the nursery this fall, be wary: some of these plants are slow to get going and need to be planted in spring to have enough time for adequate root growth before winter; others have few but long-reaching roots that also need extra time to settle in. Avoid fall planting of borderline-hardy specimens, too.

Fir (Abies spp.)
Birch (Betula spp.)
Hornbeam (Carpinus spp.)
Gas plant (Dictamnus albus)
Lenten and Christmas roses (Helleborus spp.)
Magnolia (Magnolia spp.)
Hop hornbeam (Ostrya spp.)
Oak (Quercus spp.)
Rhododendron and azalea (Rhododendron spp.)
Willow (Salix spp.)
Yew (Taxus spp.)
Hemlock (Tsuga spp.)

Plant these in fall
Maple (Acer spp.)*
Horse chestnut (Aesculus spp.)
Lady's mantle (Alchemilla spp.)
Astilbe (Astilbe spp.)
Bergenia (Bergenia spp.)
Catalpa (Catalpa spp.)
Hawthorn (Crataegus spp.)
Pinks (Dianthus spp.)
Ash (Fraxinus spp.)
Daylily (Hemerocallis spp.)
Hosta (Hosta spp.)
Daisy (Leucanthemum spp.)
Lily (Lilium cvs.)
Crabapple (Malus spp.)
Peony (Paeonia lactiflora and others)
Oriental poppy (Papaver orientale cvs.)
Cork tree (Phellodendron spp.)
Phlox (Phlox spp.)
Ninebark (Physocarpus spp.)
Spruce (Picea spp.)**
Pine (Pinus spp.)**
Hens and chicks (Sempervivum spp.)
Linden (Tilia spp.)
Elm (Ulmus spp.)
Viburnum (Viburnum spp.)

*In many parts of Canada, Japanese maples (Acer palmatum hybrids) are borderline hardy; if so, plant in spring.
**Plant up to late September; mulch well.

Read more in What to do now and Jobs in the Garden by Season