The pecan is our Texas state tree, being native to about 150 counties and capable of growing and producing in all Texas counties. The tree is popular for landscaping and as a source of nuts. Proper attention to cultural requirements and pest control will help to assure a long and productive life for home pecan trees. They do require a lot of management and care.
Nitrogen Needs
Apply 1 pound (2 cups) of 21-0-0 or 33-0-0 for each inch of trunk diameter in late March before bud break. If the tree produces a very heavy nut set in May, make a second application in late May or early June. Apply the fertilizer broadcast on the surface starting 3 to 5 feet from the trunk and extending out a few feet past the tree canopy. Water the fertilizer into the soil promptly. Avoid scattering fertilizer on sidewalks or paved driveways because some materials can cause unsightly, although seldom permanent, spotting.
Zinc
Frequent zinc sprays are essential for rapid tree growth. Trees deficient in zinc usually have small, weak leaves, highly branched (rosetted) twigs at shoot tips and, in severe cases, die back of twigs and branches. During the first 7 years, trees grow best if foliar sprays of zinc are applied at least every 2 weeks throughout the growing season of April through early August. If the trees are not growing, reduce the spray frequency. Spray mature trees with zinc at least three times between bud break in late March or early April and early June. Zinc is needed primarily by young expanding leaflets. Leaflet expansion on mature trees usually stops by mid-June. Two of several choices of zinc materials to spray are:
Zinc nitrate is formulated as a liquid. Use 2 to 4 teaspoons per gallon or 1 to 2 quarts per 100 gallons of water.
Zinc sulfate is formulated as a powder. Use 2 teaspoons per gallon or 2 pounds per 100 gallons of water. UAN liquid fertilizer (32-0-0) can be added at a rate of 1 quart per 100 gallons of the zinc sulfate solution to improve penetration of zinc into the foliage. Zinc sulfate spray can cause leaf burn on other trees in the home landscape, especially peaches, plums and other stone fruits. Zinc sprays are most effective if applied early or late in the day with little or no wind. The higher humidity under these conditions allows longer wetting and more zinc absorption. Zinc sprays pose a minimal hazard to man and animals, yet care should be taken not to contact the spray directly. Zinc sprays are not likely to stain sidewalks, houses, cars, etc.
Diseases and Insect Control
Pecans are damaged by several insect and disease pests and control measures usually are necessary to mature a good crop. Control measures are detailed in Texas Agricultural Extension publication L-1140 Homeowner’s Fruit and Nut Spray Schedule. A copy may be obtained from your county Extension office.
Large pecan trees can be a problem to spray. Hose-on sprayers are the only type that most homeowners have at their disposal that can spray very far up into the tree, but even these are limited to trees no more than 25 to 30 feet tall. Reaching the top of tall trees requires sprayers that can generate 500 to 600 psi pressure. If you do not have access to a high pressure sprayer, check with a local pest control company. Many of them apply zinc and pest control sprays.
Proper timing of spray applications is important, especially for the pecan nut casebearer and pecan weevil. Spray dates for these insects may vary each year and should be checked with the county Extension office.
Guide to Common Pecan Questions
Problem | Probable Cause(s) | Solution(s) |
The Tree | ||
Tree makes little new growth after planting | Root damage before planting | Replace tree if growth is extremely weak or cut back to a 1 foot stub during winter. |
Planted too deep | ||
Moisture stress (too little or too much) | ||
Fertilizer used in the planting hole | ||
Spring growth of young tree wilts and dies in late spring or summer. Surviving growth sprouts mainly from base of tree | Freeze damage | Prune out damaged wood. Improve fall hardening. Cut back on fall watering and don’t fertilize late. |
Older tree with weak growth, small yellowish leaves and twig dieback | Zinc deficiency | Follow fertilizer and general care recommendations. Have roots checked for nematodes. |
Poor soil | ||
Crowding | ||
Poor nitrogen | ||
Moisture stress | ||
Grass competition | ||
Nematodes | ||
Sudden tree death in the late spring or summer | Cotton root rot (especially summer death of younger trees in alkaline soils) | Replant with adapted species. |
Delayed response to severe winter freeze | Replant pecans. | |
Water-logged soil (during winter or current) | Replant with adapted species. | |
The Leaves | ||
Trees dripping sugary substance from leaves and black material coating leaves | Yellow aphids feeding on leaves | See L-1140*. |
General burn of tissue along edges and tips of leaflets | Sprinkler water on leaves | Lower sprinkler height. |
Too much fertilizer | Reduce fertilizer and water more. | |
Moisture stress | ||
Hot weather | ||
Poor quality (salty)water | ||
Black spots on leaves. | Disease most commonly scab | See L-1140*. |
Green galls (wart-like) on leaves or small twigs | Pecan scab phylloxera | See L-1140*. |
The Bark | ||
Green or yellowish fungal-like growth on the bark | Lichens | Not a problem, fungicide sprays for nut and foliage disease usually control lichens. |
Peeling woody bark | Natural part of growth and aging process | None needed. |
Deep vertical cracks | Freeze injury | Will heal depending on severity of injury. |
Very fast growth | None needed. | |
Holes in bark | soodpeckers make cone-shaped holes, usually aligned in rows | Usually not harmful. |
Borers | Treat with labeled insecticide, may indicate a weak tree from other problems. | |
The Nut | ||
Premature nut drop in summer | Poor pollination | Plant pollinator. |
Insect damage (nut casebearer, weevil, stink bug) | See L-1140*. | |
Drought stress | Water more often and deeper. | |
Random patches of dead tissue on the shucks | Disease – usually scab | See L-1140*. |
White powdery growth on the shucks | Powdery mildew | None needed, not seriously damaging |
Shuck won’t open, small white worms tunneling in shucks | Hickory shuckworm | See L-1140*. |
Shuck won’t open, but no apparent insect problem, kernel usually shriveled | “Sticktights” from drought and heat stress in September and October | Water more often and deeper especially in August and September. |
Fall freeze injury | Grow early maturing varieties. | |
Round, 1/8″ diameter hole in the shell, kernels eaten | Pecan weevil larvae (redheads) | See L-1140* |
Kernels poorly filled | Crowded trees | Thin trees. |
Old trees | Thin trees and/or avoid water and nutrientstress. | |
Shallow soil | Thin trees and/or avoid water and nutrient stress. | |
Late summer drought stress | Water more. | |
Insect damage (especially hickory shuckworm) | See L-1140*. | |
Nuts are too large | Enjoy for shade as is or graft tree to better variety. | |
Poor nutrition | Follow nitrogen and zinc recommendations. | |
Nuts sprouting before harvest | Fall drought stress | Continue watering until harvest. |
Rains during shuck opening | Harvest as early as possible. | |
Black spots on kernels | Stinkbug damage | See L-1140*. |
Fuzzy brown or tan material on surface or kernels | Stress (drought, tree crowding, old trees, shallow soil) | Water more often and deeper. |
Home Fruit Production – Stone Fruit
Fruit trees are widely adapted in Texas. However, success in growing fruit trees and in producing quality fruit doesn’t just happen. Careful attention must be given to basic management practices including site selection, variety selection, weed control, water and pest management.
Fertilization
Fruit trees can be fertilized the first year after they leaf out in the spring. Place the fertilizer at and slightly beyond the canopy edge of the tree but never against the trunk. General recommendations for regularly watered trees are included in the following table.
March | April | May | June | July | |
Year 1 | 1 cup1 balanced2 | 1 cup 21-0-0 | 1 cup 21-0-0 | 1 cup 21-0-0 | |
Year 2 | 2 cups balanced | 2cups21-0-0 | 2 cups 21-0-0 | 2 cups 21-0-0 | 2 cups 21-0-0 |
1One cup of granular fertilizer is equivalent to approximately 1/2 lb.
2Apply balanced fertilizer according to soil test recommendations, or use a common mix such as 15-5-10.
Bearing trees | ||
February–2 cups balanced fertilizer per inch of trunk diameter | ||
May–2 to 6 cups 21-0-0 per tree depending on vigor of shoot growth | ||
August–no fertilizer if trees are making vigorous growth; 1 1/2 cups 21-0-0 per tree if there is no new growth but healthy leaves; 3 cups 21-0-0 per tree if there is no new growth and leaves are yellow |
Note: If your soil pH is above 7.5, do not apply phosphorus fertilizer.
Disease and Insect Control
The best quality fruit is produced when diseases and insects are controlled. Unless an efficient spray program is maintained, it is not advisable to plant stone fruit trees. The most serious diseases are brown rot, scab and leaf curl.
Insect problems include scale, plum curculio, catfacing insects and peach tree borer. The first line of defense is good sanitation. Remove old diseased fruit and wood as it appears on the tree. Your county Extension office has information on timing, methods and materials to control diseases and insects. Many garden centers sell home orchard fruit tree sprays containing an insecticide and fungicide. Applying one of the products according to label directions usually controls most insect and disease pests.
https://aggie-hort.tamu.edu/extension/homefruit/stone/stone.html