Weekly Express-News Article
By Calvin R. Finch, PhD, SAWS Water Resources Director, and Horticulturist
Saturday, October 6, 2007
“Winter Color”

            Now, is the time plant the cool weather annuals for winter and spring color.  Flowers to consider include petunias, snapdragons, stocks, dianthus, ornamental kale, ornamental cabbage, and calendula.  Wait on pansies, cyclamen, and primula until next month.

            Snapdragons are the showiest winter annuals.  Short varieties like ‘floral carpet’ are only six inches tall, and are excellent for a border plant.  ‘Rockets’ are the tallest selection.  They reach three feet tall.  Use them in the cut flower garden, as background in the flower bed or specimen plants in large containers.  Tomato cages work well to support the top heavy plants.  There are mid-size selections of snapdragons as well.  They reach 14 – 18 inches and make good bedding plants.

            Snapdragons bear their blooms on stalks above the foliage.  The colors are very intense.  Select from red, purple, violet, white, yellow, orange, salmon or pink. If you get your transplants in early this month there is a good chance you will have a bloom period this autumn.  If there is some serious cold weather in late December or January, there will be a bloom respite until March.  March through May is when the snaps really make their best display.  In many neighborhoods, including mine, deer do not eat snapdragons. 

            Sometime in May when warm weather arrives they are attacked by the fungal disease, rust and they quickly decline. Stem borers can also be a problem.  Prevent them with a preventative insecticide spray every two weeks or spray acephate at the first sign of borers.

            Stocks are not nearly as showy as snapdragons, but they are attractive and have a pleasant fragrance.  There are a number of selections of stocks available by seed, but nurseries usually only offer one variety in transplant.  The flowers are pastel shades of pink, white, lavender, and red.  The blooms are arranged on the stems interspersed in the foliage.  They have an old-fashioned look.

            In 2006/2007, stocks responded better to the autumn weather conditions than the other winter annuals.  They were the steadiest bloomer in many gardens.  Stocks do make a good cut flower.  The blooms last a long time and the fragrance will perfume the room where they are displayed.

            Snapdragons and stocks require full sun to perform well, ornamental kale and ornamental cabbage can tolerate some shade.  Instead of flowers, the two plants rely on foliage to provide winter color.  They come in versions of red-green and silver-green.  The foliage can be tightly arranged with smooth edges or more open with fringed edges.  The ornamental cabbage is especially disciplined looking.  Planted in rows or as a border they remind me of soldiers on parade. 

            Ornamental kale and cabbage are most attractive after they gain some size from mid-winter through late spring.

            Dianthus are also called “pinks.”  They are a relatively short plant that reach eight inches tall.  Dianthus have small flat flowers in white, pink, red, lavender, and every bicolor possible within that combination of colors.  Dianthus are a steady bloomer from autumn to spring and even into the summer.  Use them as a border or bedding plant.  They are a favorite butterfly food source.

            Petunias in the North are summer flowers, but in San Antonio they are cool weather plants.  They bloom especially well in the fall and in the spring.  Plant them now for red, blue, violet, white, light yellow, pink, and bicolor blooms.

            Calendula are daisy-like flowers that warm up the winter garden with yellow and orange blooms.  They are a favorite of butterflies and make good cut flowers.  Calendula reach about 12 inches tall.  Use them as a bedding plant in full sun or in the cut flower garden.

            Pansies bloom from the day you plant the transplant until late spring.  Wait until late October or November to plant them.  The best shade loving winter bloomers, cyclamen, and primula also do best if planted when the temperatures cool later in the month. 

            To prepare your garden for cool weather annuals, add one – two inches of compost and a cup of slow release lawn fertilizer per 50 square feet of bed.  Till or shovel the compost into the upper six inches of bed.  Water the transplants in with a hand-held water wand at planting and mulch with leaves or other fine material about two inches deep.  Water when the soil dries under the mulch.