Cooling temperatures and increasing rain are two reasons that make fall a good time to plant most plants.
As summer heat hands off to falling leaves, thoughts of the outdoors tend to turn toward Halloween decorating rather than planting, which is seen more as a spring task. This is ironic, since in many ways planting in fall is better timing than spring planting.
Fall planting gives two cooler, damper growing periods – fall and spring – before a new plant faces blast-furnace summer conditions. Fall really is a good time to plant most things because:
- Shorter days, less intense sunlight, more rain, and the cooler temperatures of early fall mean less stress (i.e. “transplant shock”) for plants being evicted from their cozy pots into the untamed ground.
- Newly planted plants tend to lose less moisture through their leaves in fall than in summer, which lowers water demands.
- Bugs and diseases that are in high gear during summer mostly wind down and/or disappear to hibernate as fall progresses.
The bottom line: In most of the United States, the soil stays warm enough to encourage root growth for at least another 6 to 8 weeks, so don’t be too quick to pack away the shovels.
Shop knowledgeably: When plant-shopping this time of year, you’ll run into both fresh fall stock from growers, as well as spring leftovers that may not have had the best care over summer. It is wise to:
Fall-purchased plants sometimes have circling roots from a summer’s worth of growth confined in a pot.
© George Weigel
- Check the leaves and branches for bug damage, leaf spotting, leaf streaking, and other signs of potentially ongoing trouble. Think twice before buying any of these.
- If the leaves are just tired and browning, or if the spent flower stems just haven’t been snipped, or if the plant is a bit gangly from spending the summer in a small pot, that’s a different story… especially if the price tag says 50% off.
- What counts most is the condition of the roots. If you’re in doubt about the health of a potential plant, gently slip the plants out of their pots and look for roots that are fleshy and creamy or white, not black and mushy, or brown and shriveled. The latter means the plants were either over- or under- watered. This time of year, you might also run into roots that have grown to fill the pots, and begun circling around the inside. A little of that is fine, just fray out the circling roots before planting, or even make two or three vertical cuts through the roots to break up a too-tight mass. If the roots are so badly circled that you can’t even get the plant out of the pot, that’s of more concern. It doesn’t mean the plant won’t transplant and live happily ever after… but it lowers the odds.
Here are plantings you can tackle now and in the coming weeks:
Things you can plant now to enjoy right away
- Fall-blooming perennial flowers such as mums (Chrysanthemum spp.), asters (Aster spp.), sedum (Sedum spp), Japanese anemone (Anemone x hybrida) and leadwort (Ceratostigma plumbaginoides).
- Perennial flowers with colorful foliage that’ll look good until frost and then bloom next year, including variegated liriope (variegated Liriope spicata & L. muscari spp.),variegated Jacob’s ladder (Polemonium caeruleum ‘Brize D’Anjou’ or ‘Gateway to Heaven’), variegated Siberian bugloss (Brunnera macrophylla cultivars), coralbells (Heuchera cultivars), foamflowers (Tiarella spp.), foamybells (X Heucherella), leadwort (Ceratostigma plumbaginoides), hardy geraniums (Geranium spp.), hosta (Hosta spp. and cultivars), Japanese painted ferns (Athyrium niponicum cultivars), bugloss (Ajuga spp), deadnettle (Lamium spp.) and yucca (Yucca spp.).
- Hardy herbs with colorful foliage, such as purple (Salvia officinalis ‘Purpurea’) or pineapple sage (S. elegans), golden oregano (Oregano vulgare ‘Aureum’) and golden (Thymus serphyllum’Aureus’) or silver thyme (T. vulgaris ‘Argenteus’).
- Cold-hardy “winter” annuals, such as pansies and violas, and in milder locations dusty miller (Centaurea cineraria), annual phlox (Phlox drummondii), nemesia (Nemesia strumosa cultivars), snapdragons (Antirrhinum cultivars), and annual dianthus (Dianthus chinesis).
- Cold-tolerant fall foliage plants that you toss at winter’s end, such as ornamental cabbage and kale (Brassica oleracea).
Kale is one colorful plant that can only be planted in fall and looks its best then as well.
© George Weigel
Things you can plant now that will peak in fall
- Trees with great fall foliage, such as maple (Acer spp.), stewartia (Stewartia spp.), sweetgum (Liquidambar styraciflua), blackgum (Nyssa sylvatica) dogwood (Cornus spp.), Persian parrotia (Parrotia persica)and sourwood (Oxydendron arboreum), sasanqua camellia (Camellia sasanqua).
- Shrubs with great fall foliage, such as fothergilla (Fothergilla gardenia), dark-leaf ninebark (Physocarpus opulifolius), Virginia sweetspire (Itea virginiana), witch hazel (Hamamelis spp.) and viburnum (Viburnum spp.).
- Trees and shrubs with colorful fall berries, such as crabapple (Malus spp.), dogwood (Cormus spp.), hawthorn (Crataegus spp.), junipers (Juniperus spp.), hollies (both evergreen (Ilex spp) and winterberry I. verticillata) types), beautyberry (Callicarpa spp.), chokeberry (Aronia spp.) and viburnum (Viburnum spp.).
Species you can plant now to enjoy next spring
- Spring-blooming bulbs, such as snowdrops (Galanthus spp.), crocuses (Crocus spp.), Siberian squill (Scilla siberica), glory-of-the-snow (Chionodoxa spp), daffodils (Narcissus spp.), hyacinths (Hyacinthus orientalis), tulips (Tulipa spp.), grape hyacinths (Muscari spp.) and ornamental onions (Allium spp.).
- Winter-hardy, early-blooming perennial flowers, such as Lenten rose (Helleborus spp. & cultivars), Siberian bugloss (Brunnera macrophylla), creeping phlox (Phlox subulata), Canadian windflower (Anemone canadensis), primroses (Primula spp.), and lungwort (Pulmonaria spp.).