Timely Tips: March 2015

February 24, 2015

clock_LGWe’ve said it before, but it never applies like it does in March: half of your success in gardening involves doing the right things. The other half involves doing them at the right times. Here are this month’s assignments.

Plant: Finish planting cool-season vegetables (cabbage, broccoli, Irish potatoes, leafy and root crops) in Central and North Texas now. Warm-season types (beans, corn, squash, cucumbers, melons, tomatoes and then peppers) can be planted soon in far South Texas; plant beginning with average date of last killing freeze and extending two to four weeks beyond it in North Texas. Finish planting cool-season annual flowers early in month, including petunias, pansies, snapdragons, calendulas, stocks, sweet alyssum, English daisies, pinks, larkspur and poppies. Dig and divide summer- and fall-flowering perennials such as mums, mallows, cannas, coneflowers and fall asters immediately. If they have started new growth, it’s probably too late. Choose spring-flowering shrubs and vines as they are in bloom in local nurseries, including azaleas, forsythia, bridal wreath, wisteria and Carolina jessamine.

Prune: Tidy perennial gardens immediately to remove old stubble before spring growth begins. Compensate for roots lost in transplanting by thinning new balled-and-burlapped plants by 30 percent and bare-rooted plants by 40 to 50 percent. Finish pruning shade trees immediately – before buds start to swell. Remember that you must never “top” crape myrtles for any reason. Reshape spring-blooming vines, shrubs after they finish flowering.

Fertilize: High-phosphate, root-stimulator fertilizer monthly to new balled-and-burlapped and bare-rooted plants. From that point on, however, you will probably not need to apply any more phosphorus to most Texas soils. Apply high-nitrogen or all-nitrogen lawn fertilizer to warm-season grasses mid-to late March in South Texas. Wait until April in North Texas. Use same lawn-type fertilizer for shade trees, evergreen and summer-flowering shrubs, groundcovers, also for spring-flowering shrubs and vines, immediately after they have finished blooming. Pecans with all-nitrogen fertilizer monthly through May. Roses with monthly application of specialty rose food.

On The Lookout: Apply pre-emergent weedkiller granules such as Halts or Dimension, to prevent germination of crabgrass and grassburs, immediately in South Texas, by mid-month in North Texas, and late in March in Panhandle. Repeat application 90 days later for season-long control. Apply broadleafed weedkiller spray to non-grassy plants such as dandelions, clover and chickweed, among others. Begin rose spray program for blackspot, powdery mildew, aphids and thrips. Snails, slugs and pillbugs will eat holes in leaves of many types of plants. Control with Sevin dust or baits. Protect pears, pyracanthas, cotoneasters and apples against fire blight invasion. Spray with agricultural streptomycin while plants are in full flower. Prune out diseased wood, as it occurs, disinfecting your pruning tools with a 1:9 solution of chlorine bleach to water between cuts. Continue fruit spray program for insects, diseases until harvest. Learn what rose rosette virus damage looks like when it attacks rose plants. Typical symptoms are vigorous, clubby stems that are covered with multitudes of thorns. Flowers fail to open properly. If you see evidence of the disease, remove all of the affected plants immediately, roots and all. Put them into black plastic trash bags and send them to the landfill. The virus is spread by a microscopic mite, and there is no control for the disease and no way to eliminate the mites.