Extension Educator, Horticulture
Spring initiates tremors in many gardener's hands. Tremors that aren't registered on the Richter scale, but on the pickup scale that is determined by the number of piles of tree trimmings laying in yards. The following plants should be pruned in early March before the buds open.
Remember when pruning grape vines, the grapes are produced from the buds of one year old canes which are about 1/4 to 1/3 inches in diameter and are reddish brown. When properly pruned, 80 to 90 percent of the grape wood is removed every year. Now you know why people can make so many grapevine wreathes.
Grape vines with a main trunk and four canes are often trained to a two-wire trellis. Before pruning, select four strong lateral one year old canes (arms) that are close to the trellis and mark with a ribbon or colored tape. The largest and heaviest canes are not good fruit producers. Tie the four arms to the trellis. Choose four more lateral canes to become the arms for next year. Remove everything else. Prune off the ends of this year's arms so that 10 to 15 buds remain on each of the arms and only two buds are left on the renewal spurs (next year's arms).
Remove all short and weak canes. The large remaining canes are thinned to four to eight inches apart. The canes are cut back to five to six feet tall or if no support is provided three to four feet tall. The canes that produced last year should be removed anytime after harvest, or remove them now. Canes are productive only one year and the new growth will produce the next year's harvest. The exception are everbearing raspberries such as 'Heritage' which produce a second crop in the spring on the canes that produced last fall.
Peaches and apples especially require annual pruning to remain productive. If left unpruned, fruit production tends to be limited to the top and outer portions of the tree and every other year. Harvesting becomes a real chore left to the giants of the family. Peaches are pruned just before bloom and during bloom.
Apples should be pruned now before the buds show green tips. Remove any dead, diseased or broken branches. Sterilize tools with alcohol or bleach after each cut.
Branches should not grow into each other or rub. If two branches of about equal size form a narrow 'V' attachment, then eliminate one of the branches. The strongest branch attachments form 40 to 90 degree angles with the trunk.
Dormant oil spray can also be applied now to apples to control San Jose scale, eggs of European spider mites and eggs of rosy apple aphid. Spray only when temperature will not drop to freezing for 24 hours following spray application.
Peaches should be sprayed now with captan or multipurpose fruit spray if peach leaf curl has been a problem. Peach leaf curl appears as a thickening, curling and puckering of leaves. Fruits become swollen and deformed. Fruit may be hollow with thick spongy flesh. Dormant fungicide spray on peaches is critical since it is the only spray that will control this disease. Be sure to read and follow all label directions.
Publications available for a small fee from the University of Illinois Extension office: Growing Small Fruits in the Home Orchard; Growing Tree Fruits in the Home Orchard; Pruning and Care of Trees and Shrubs. Bring your garden questions to the Master Gardener display at the Plant Sciences greenhouses during the University of Illinois College of Agricultural, Consumer and Environmental Sciences Open House from 9am-4pm on Friday, March 3 and Saturday, March 4.