Things to Do in the Late Winter Lawn and Garden

By Andy Wilson, Senior Extension Specialist, Pinellas County Extension

The severe (by our local standards) cold in early January damaged many cold tender landscape plants. For most cold-damaged plants it is good idea to delay pruning until after the danger of additional freezes is past (late February). At that time the plants can be cut back to living wood. To determine where the wood is alive, scratch the bark of a branch, beginning out toward the branch tip, to expose the cambium layer that lies just under the bark. Where this layer is green the wood is alive, while it will be brown or black where the wood is dead. If you’re a nervous pruner, remember that, given time, the plants will resprout on their own where the wood is alive, removing all doubt.

With palms, avoid the temptation to immediately trim damaged leaves. Instead, wait to remove damaged leaves until the palm has produced 2 or 3 new leaves. You can, however, go ahead and apply copper fungicide. The copper fungicide should be directed to the spear leaf and bud area. Before spraying, gently tug on the spear leaf, the newest unopened frond, to see if it easily pulls out. If it does, remove it and be sure to direct the copper fungicide spray down into this area using the force of the spray to help clean out any decayed material. Repeat the copper fungicide application in 10 days. Although it has not been fully proven, it is thought that this treatment may increase the chances that cold-damaged palms will survive by protecting the bud from bud-rotting bacteria and fungi. If the bud dies, it is only a matter of time before the palm dies also, since it is from this bud that all new growth of the palm is produced. Patience is important since it may take up to 7 months for new growth to emerge, and this is only way to tell if the bud has survived. More information on treatment of cold-damaged palms can be found here: http://edis.ifas.ufl.edu/mg318
There are other tasks in the winter lawn and landscape. Here are a few:

Apply crabgrass control- Crabgrass is one of the most common weed problems in lawns in our area. Probably the most practical way for homeowners to control it is by applying a preemergence herbicide in early February. Preemergence herbicides prevent weed seed from germinating. Timing of the application is important. Once the seeds have germinated they are no longer susceptible to preemergence herbicides. Among available preemergence herbicides for use on both bahiagrass and St. Augustinegrass are some containing benefin, benefin+oryzalin, benefin+trifluralin, napropamide, oryzalin, pendimethalin and prodiamine. Be sure to read and follow all label directions. Also, remember that a healthy lawn is more resistant to weed invasion than one that is thin due to improper fertilization, uncontrolled disease or insect problems, mowing too closely or other problems caused by pests or poor care. Proper maintenance is an important part of an overall weed management program.

Fertilize Citrus- Fertilization of established citrus trees can be important for the best possible fruit production. For young trees, a balanced fertilizer like an 8-8-8 analysis can be used. For older trees, a fertilizer with less phosphorous (the middle number of the 3 numbers of the fertilizer analysis) such as a 12-0-12 or 15-0-14 can be used.

Cut back ornamental grasses- Most ornamental grasses can be cut back sometime in February. At the same time, remove any accumulation of dead growth from them. This helps to stimulate vigorous new growth. In the wild, many grasses are re-invigorated by periodic fires. Cutting ornamental grasses back annually has much the same effect in the landscape. More information on care and selection of ornamental grasses can be found here: http://edis.ifas.ufl.edu/ep233

Cool season annuals- Pots of cool season annuals can add color to freeze damaged landscapes. Cool season annuals should, with some care, remain attractive until about May when high temperatures begin to take their toll. Some of the possible choices include pansy, petunia, calendula and dianthus. If the pots can be moved to a protected area if more cold threatens, the list can be expanded to include many more cold tender plants including impatiens, begonias, and salvia. Use a well drained-potting mix and be sure that any containers being used have drain holes in them. The containers can be fertilized with controlled-release fertilizers or water-soluble fertilizers. When repeat applications will be needed will vary with the product. Some controlled-release fertilizers will not need to be reapplied for several months while water soluble fertilizers may need to be reapplied every one to two weeks. Follow the label directions.

Roses- Bush roses can be given their major pruning of the year in February. Prune back branches that are crossed and rubbing, dead or diseased wood and branches smaller than the diameter of a pencil. Old canes that no longer flower well can be removed. Prune back the remaining canes by 1/3 to 1/2 of their current length. Pruning encourages the production of new growth. Since roses bloom on new growth this annual pruning is necessary for the best flowering. It is a good idea to remove all the remaining leaves on the bushes after pruning and then spray with a fungicide, such as copper fungicide. Spraying for black spot fungus will be needed on a weekly basis once new growth emerges. Effective controls for black spot include products containing triforine, chlorothalonil, mancozeb, myclobutanil or propiconazole. Spraying for black spot is unfortunately a major part of the work needed to successfully grow roses in Florida. Begin fertilizing roses monthly at this time also. More information on growing roses in Florida can be found here: http://edis.ifas.ufl.edu/ep339

Working in the lawn and garden is great way to get some exercise and fresh air and clear the mind, and it can have a positive effect on property values. What’s not to like about all that?