'Groundwork' for Feb. 17, 2013

Prune newly planted and young fruit plants to develop strong branches capable of supporting a bountiful fruit crop. The most common fruits that benefit from pruning in home landscapes are blackberries, blueberries, figs, peaches, pears, plums, muscadine grapes and sometimes citrus.

Annual pruning maintains overall plant size, decreases disease problems, improves fruit quality, and aids in harvesting.

If you have older fruit trees that have been neglected, it is best to reduce the amount of existing growth over time in increments with the judicious use of thinning cuts.

Thinning cuts, or those that remove wood at its base or point of origin, allow the size and shape of the tree to be maintained. Thinning cuts can reduce the tree size while still maintaining the natural shape of the canopy.

The first step in pruning a neglected tree is to remove all diseased or dead material. Next, remove the very upright, extremely vigorous shoots that are shading the interior. Then remove the limbs that are joined to the trunk at a narrow angle and leave the limbs with wider crotch angles.

In some cases, having too many scaffold limbs may be a problem. Excess wood can be removed to leave three to five lower scaffolds with fairly wide crotch angles spaced evenly around the tree. Extensively pruned trees should not be fertilized the following spring. This will prevent excessive, unproductive growth from redeveloping.

With a good, working knowledge of basic principles of plant response to pruning, proper pruning techniques and clear objectives for the tree, fruit tree performance can be improved while maintaining the beauty of the tree.

To schedule a home pruning demonstration in East Baton Rouge Parish during February, call LSU AgCenter Extension agent Bob Souvestre at (225) 763-3990.

Weed reduction

Nonherbicide weed control in landscape beds is primarily done through mulching and barriers such as landscape fabric.

Proper mulching is the single-most important technique we use in reducing weed problems in beds. Once weeds begin to grow, the nonherbicide control is hand weeding.

Using herbicides should be approached very seriously. After all, you are introducing into your landscape chemicals that are designed specifically to kill plants.

It is entirely possible that you could seriously damage your lawn, trees, shrubs and other landscape plants if you use them improperly. That said, they are useful tools in our efforts to manage weeds in our landscapes if used properly.

There is something else you need to realize about herbicides. They are a tool you can use in your continuing efforts at weed control.

In the overwhelming majority of situations, you will need to apply herbicides more than once for effective control. Make sure you are using the right herbicide, and then keep at it.

Identify the weed. Different herbicides will control different weeds. If you use the wrong herbicide, you waste effort and money.

When discussing herbicide options, it’s important to learn some terms.

Preemergence herbicides — These are applied to weed-free areas to prevent annual weed problems by killing germinating weed seeds.

Postemergence herbicides — These are applied to actively growing weeds to control a current weed problem.

Selective herbicides — These will just kill the weed and not the ornamentals or turf when applied over all the plants in an area. These are commonly used in lawns, but there are also products useful in weed management in beds. It is critically important that you completely read and understand the label of any herbicide you use.

Read the entire label before you purchase a product. If you use it improperly, great damage can be done to landscape plants.

Treating weeds

Broadleaf weeds and annual bluegrass infesting St. Augustine, centipede, zoysia and dormant Bermuda grasses can be managed with applications of atrazine herbicide.

February and March are good months to spray winter weeds while they are still actively growing. Also, herbicides containing three-way mixtures of 2,4-D plus dicamba plus mecoprop can be used for winter broadleaf control in all Southern turfgrasses this time of the year.

Since weed-and-feed products usually contain high levels of nitrogen fertilizer, application should be delayed until the appropriate times for applying nitrogen-containing fertilizers for your area.

Weed-and-feed products can be substituted as your first application of fertilizer during the early spring. Lawns may be fertilized in the Baton Rouge early to mid-April.

What to do

Some things to do this month include trimming ground covers and ornamental grasses to freshen their look by removing brown foliage before tender new growth commences.

Finish fertilizing citrus trees and other fruits. Remove unwanted growth from below the graft.

Treat brown patch, or large patch, in lawns. This disease can come and go throughout the winter if the weather is mild.

Treat with fungicides containing myclobutanil, propiconazole, pyraclostrobin, thiophanate-methyl, triticonazole and azoxystrobin.

Prune evergreen shrubs before spring growth shows. Stagger the height of cuts and cut branches where they join another.

This will help thin the plant canopy to permit increased air flow and maintain overall size and shape.

Got a gardening question? Write to Bob Souvestre, horticulturist with the LSU AgCenter, at Burden Center, 4560 Essen Lane, Baton Rouge, LA 70809, or email to bsouvestre@agcenter.lsu.edu, or call Master Gardeners at (225) 763-3990.