Gardener: These annuals will thrive as the weather cools

Joe Lamp'l

If it hasn't happened already, you're going to wake up some morning soon to a shimmering coating of frost on the garden. That usually signals the beginning of the annual fall ritual of "garden cleanup" -- and the end of the flowers.

But there are many plants that will not only tolerate a little frost, they'll thrive in the chill. Avoid exposure by planting away from windy areas and low spots where cold air tends to pool, and keep plants healthy and vigorous to handle the stress of cold weather.

Here are some annuals that love the cold weather:

-- African daisy (Gazania rigens). This colorful ground cover is easy to grow and very drought-tolerant once it's established. African daisies come in many color combinations, but usually always show off dark bands that accentuate the flower's flat central disc. Thick, fuzzy gray leaves have silvery undersides. They can take several hard frosts. Most African daisies only open in full midday sun, but breeders have developed the Daybreak Series that blooms in lower-light conditions. (Orange, yellow, violet, pink and red blooms summer to frost; close down around 15 degrees F.)

-- Kale (Brassica oleracea). This edible relative of cabbage, broccoli and cauliflower makes a colorful statement in the autumn garden. The showy, ruffled and fringed leaves hate the heat, but will thrive in cold weather. Temperatures below 50 degrees intensify the color and the peppery flavor. Wait to set out full-grown plants until fall, when the worst of the summer heat is past. (Pink, cream, white, red and green leaves early spring and fall; full sun; closes down below minus-10 degrees.)

-- Pansy (Viola hybrids). One of the most popular winter annuals in the South, and a profuse bloomer in the spring and fall in the North as well. Their facelike flowers, held above shiny leaves, make a great front-of-the-border plant. Cut back by one-third when they start to stretch in the heat. Keep deadheaded to prolong flowering. (Flower in most colors and fascinating combinations and patterns in early spring to summer and again in fall to winter; full sun to part shade; close down at minus-20 degrees if heavily mulched.)

-- Pot marigold (Calendula officinalis). This proven garden favorite makes tons of blooms, and with some deadheading will flower to frost. Pot marigolds wilt a bit in the high heat of summer, but cut them back by half in early fall and they'll perk back up again when the weather cools. (Cream, apricot, orange and yellow blooms summer to fall; full sun to part shade; close down around 30 degrees; the seeds can survive the coldest winters in the soil and rebloom next year.)

-- Snapdragon (Antirrhinum majus). Timeless garden favorite with a variety of flower shapes, including traditional, butterfly and doubles, and sizes from dwarf to tall and even a few trailing varieties. After they flower, shear back by half to get a second bloom and to keep them bushy and full. (Bloom in nearly every color in early summer and again in fall; full sun to part shade; close down at minus-20 degrees if mulched with dry leaves or straw.)

-- Stock (Matthiola hybrids). Stock's tall spikes of old-fashioned blooms make great cut flowers and fill a room with a spicy scent. They need temperatures below 65 degrees to bloom. They like moist, well-drained soil but aren't picky, even tolerating sandy and clay soil. Keep the soil moist by mulching, and deadhead to keep stock blooming right up to a heavy frost. (Blooms white, pink, rose, lavender, purple or red late spring to early summer and again in late summer to fall; full sun to part shade; closes down in the mid-20s.)

Joe Lamp'l, host of "Growing a Greener World" on PBS, is a master gardener and author. For more information, visit