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Apple and Pear

Apple and pear trees are subject to serious damage from pests. As a result, a preventive spray program is needed. The following practices will improve the effectiveness of the pesticides and may lessen the need for sprays.

  • Plant disease-resistant varieties. This method of disease control is especially important for fire blight, where chemical control options are limited. Varieties resistant to cedar-apple rust, scab, and powdery mildew also are available and will potentially reduce the need for sprays.
  • Rake and destroy leaves in the fall if apple scab or pear leaf spot are problems. The fungi that cause these diseases can survive through the winter in infected leaves.
  • Remove diseased galls from cedar trees. Spores from these cedars can infect apples, causing cedar- apple rust. Elimination of the source of spores (cedar trees) is effective but not always possible. Where cedars are part of an established landscape, remove and destroy all galls caused by the rust fungus on cedars in the late fall. Inspect the cedars again in the early spring during or just after a rain when the orange, gelatinous fungus growth from any remaining galls is highly visible. Remove these galls.
  • Prune trees according to recommendations to improve control of all aboveground diseases. In well-pruned trees, air circulation and sunlight penetration are improved. This helps to control diseases by promoting rapid drying after rains and dew. Penetration of sprays into the canopy also is better if the trees are well pruned.
  • Prune out and destroy all dead or diseased shoots and limbs during the dormant season. This helps to reduce fire blight, fruit rots, and certain leaf spots, as the organisms that cause these diseases can survive through the winter in the wood. Removing mummified (dark, shriveled, dry) fruit helps to prevent the overwintering of the fruit rot organisms.
  • Prune out fire blight–affected shoots and blossom clusters during the growing season only as symptoms appear. Prune during dry weather and sterilize tools between cuts.
  • Control weeds that may harbor insect pests.
  • Use only copper, sulfur, and streptomycin sulfate disease control products on pear trees. Streptomycin sulfate can be used for fire blight as found in table 1.1. Copper and sulfur can be used for leaf spot, scab, quince rust, and other diseases as directed on the label. Both copper and sulfur can injure pears, so read the label carefully.

Table 1.1. Disease and Insect Management for Home Orchards—Apple and Pear (cannot use captan or myclobutanil on pears; use only copper and sulfur)

Time of ApplicationPest ControlledMaterial to Use1Comments
Delayed dormant: when leaves start to protrude from budsFire blightCopperRefer to label for specific application timing.
Delayed dormant: when leaves start to protrude from budsAphid, mite, scaleHorticultural oilApply three times during the dormant season.
Bud break: from 1⁄2 inch long green leaves to tight clusterScabCaptan
Bud break: from 1⁄2 inch long green leaves to tight clusterAphid, mite, scale, plant bugs, leafminerMalathion or permethrinRepeated use of pyrethroids such as permethrin will increase mite populations. Malathion rarely induces secondary pest populations.
Pink: just before blooms openScab, cedar apple rustCaptan or myclobutanilIf cedar apple rust has been a problem, use myclobutanil in this stage, petal fall, and first cover sprays.
Pink: just before blooms openAphid, mite, scale, plant bugs, leafminerMalathion or permethrin
BloomFire blightStreptomycinIf fire blight has been a problem, apply streptomycin every 3–4 days during bloom.
BloomDo not apply insecticides during bloom to protect pollinators.
Petal fall: when most of the blooms have fallenScab, cedar apple rust, powdery mildewCaptan or myclobutanil
Petal fall: when most of the blooms have fallenCodling moth, leafroller, leafhopper, plum curculio, Oriental fruit mothMalathion or permethrinPermethrin can provide some control of stinkbugs as well.
First cover: 7 to 10 days after petal fall sprayBitter rot, white rot, cedar apple rust, scabCaptan or myclobutanil
First cover: 7 to 10 days after petal fall sprayCodling moth, leafroller, leafhopper, plum curculio, Oriental fruit moth Malathion or permethrin
Remaining covers: at 2-week intervals until harvest restriction dateBitter rot, white rot, sooty blotch, fly speckCaptan
Remaining covers: at 2-week intervals until harvest restriction dateCodling moth, plum curculio, Japanese beetleMalathion or permethrin

1Insecticides and fungicides can be mixed in the same tank and sprayed together.

Peach, Plum, and Nectarine

Peach, plum, and other stone fruits are commonly affected each year by several insect and disease problems. A spray program is therefore needed for successful fruit production. The following sanitation and cultural practices will improve the chances of success and may lessen the need for sprays.

  • Prune trees according to recommendations to allow better air circulation and sunlight penetration. Pruning helps to control diseases by promoting rapid drying after rains and dew. Penetration of sprays into the canopy is also better if the trees are well pruned.
  • Remove and discard old mummified fruit left hanging in the tree or laying on the ground. Mummified fruit is an important overwintering site of the brown rot fungus.
  • Control black knot of plum trees by removing knots before they begin to produce spores. In late winter, prune out and destroy these rough, black swellings or galls that develop on twigs and branches.
  • Avoid planting peach varieties that are highly susceptible to bacterial spot, as there are few options for control of this disease. Examples of highly susceptible cultivars are Elberta, Halehaven, Rio-Oso-Gem, O-Henry, Cresthaven, and Sunhigh.
  • Control broadleaf weeds with regular mowing to control insect pests.
  • Remove fruit damaged by insect feeding.

Table 1.2. Disease and Insect Management for Home Orchards—Peach, Plum Nectarine

Time of ApplicationPest ControlledMaterial to Use1Comments
Dormant: late fall to early spring before bud swellPeach leaf curlChlorothalonil or copperFungicide application is needed for peach leaf curl only if there is a history of this disease.
Dormant: late fall to early spring before bud swellAphid, mite, scaleHorticultural oilApply three times during the dormant season.
Delayed dormant: when buds swellAphid, mite, scaleHorticultural oilDo not apply when temperatures are below 40°F or are predicted to fall below 40°F within 24 hours.
Pink: Just before blooms openBlack knot of plumCaptan or chlorothalonil Fungicides are needed for plum trees ony if black knot is a problem. Remove and destroy all signs of black knot during the dormant season.
Pink: Just before blooms openLesser peachtree borer, peachtree borer, plum curculio, Oriental fruit moth Malathion or permethrinTreatment provides some control of leaffooted bug and stinkbugs. Permethrin can be used only on peaches.
BloomDo not apply insecticides during bloom to protect insect pollinators.
Petal fallBrown rot, scabCaptan, chlorothalonil, or sulfur
Petal fallScab, lesser peachtree borer, peachtree borer, plum curculio, Oriental fruit mothMalathion or permethrinRepeated use of pyrethroids such as permethrin will increase mite populations. Malathion rarely induces secondary pest populations.
Shuck split: when flower shucks begin to splitBrown rot, scab, black knot of plumCaptan, chlorothalonil, or sulfurDo not apply chlorothalonil after shuck split.
Shuck split: when flower shucks begin to splitLesser peachtree borer, peachtree borer, plum curculio, Oriental fruit mothMalathion or permethrin
Cover sprays: repeat at 10–14 day intervalsBrown rot, black knot of plum, scabCaptan
Cover sprays: repeat at 10–14 day intervalsLesser peachtree borer, peachtree borer, plum curculio, Oriental fruit mothMalathion or permethrinRepeated use of pyrethroids such as permethrin will increase mite populations. Malathion rarely induces secondary pest populations.
Preharvest sprays: 2–3 weeks before harvest2Brown rotCaptan or propiconazoleThese are critical sprays for brown rot control. Propiconazole is more effective than captan for brown rot control.
Preharvest sprays: 2–3 weeks before harvest2Lesser peachtree borer, peachtree borer, plum curculio, Oriental fruit moth, stinkbug, leaffooted bug, grasshopperMalathion or permethrin or permethrinSpray permethrin 14 and 7 days prior to the anticipated harvest date.

1Insecticides and fungicides can be mixed in the same tank and sprayed together.

Blueberry

If diseases have been a problem in past years, captan can be used at intervals of 7 to 10 days from bud break to harvest. If mummy berry disease has been a problem, rake the area beneath and around plants to collect or bury any mummified fruits from the previous year’s crop. This will help to reduce the incidence of mummy berry. To reduce dieback diseases, prune out and destroy dead twigs and branches.

  • Monitor for insects and spray as needed.
  • Monitor for spotted wing drosophila (SWD), which is a new pest that infests developing fruit. Make sprays once a week to control or prevent SWD. If maggots are found, pick all blue and ripe fruit from the plants. Also remove fruit from the ground. Burn the fruit or seal it in a bag and take it off-site for disposal.
  • Apply insecticidal sprays regularly if the orchard was previously infested with SWD.

Table 1.3. Disease and Insect Management for Home Orchards—Blueberry

Time of ApplicationPest ControlledMaterial to Use1Comments
Dormant seasonScaleHorticultural oilDo not apply horticultural oils within 2 weeks of sulfur applications.
Delayed dormant: when buds swellGall midge, thripsMalathion or spinosad
Petal fall: until 30 days after bloomLeafhopperPermethrin or pyrethrins
Cover sprays: from 1 month after bloom until preharvestJapanese beetleCabaryl or permethrin or acetamipridApply as needed.
Bloom: appearance of berry color to harvest2Spotted wing drosophilaMalathion or acetamiprid or spinosadUse malathion in rotation with acetamiprid and spinosad.

1Insecticides and fungicides can be mixed in the same tank and sprayed together.

2Refer to product labels for preharvest interval (PHI) or the number of days between final spray and harvest.

Blackberry

An intensive spray program is generally not needed for blackberry plants. Fungicide and insecticide sprays can be applied as needed. The following sanitation practices will reduce the need for pesticide sprays.

  • Remove and destroy nearby wild blackberries to reduce the source of pests.
  • Remove and destroy fruiting canes immediately after harvest.
  • Promote rapid drying and good air circulation within the canopy by controlling weeds and keeping the plants properly thinned.
  • Pick berries often during the harvest period to minimize the amount of overripe fruit. This will reduce problems with berry rots, sap beetles, wasps, and fruit flies.
  • Promptly dig up and remove or destroy plants infected with orange rust as soon as symptoms appear in spring. Symptoms of orange rust include willowy growth of new shoots and the presence of orange spore pustules on the undersides of the leaves.
  • Remove and destroy infected canes before blooms begin to open to control the spread of rosette. You can recognize rosette by the presence of clusters of stems on fruiting canes that produce a bunchy appearance. Flower sepals are extended and pinkish in color on plants with rosette.
  • Make sprays once or twice weekly to control or prevent spotted wing drosophila (SWD), which is a new pest that infests developing fruit.

Table 1.4. Disease and Insect Management for Home Orchards—Blackberry

Time of ApplicationPest ControlledMaterial to Use1Comments
PrebloomAphid, Japanese beetle, fruitworm, stink bugMalathion
Early to midbloomAnthracnose, rosette, rustsCopper, myclobutanil, or sulfurApply a fungicide if anthracnose, rosette, or rust has been a problem in the past.
Early to midbloomDo not apply insecticides during bloom to protect insect pollinators.
Cover sprays: every 2 weeks postbloomAnthracnose, rosette, rustsCopper, myclobutanil, or sulfurApply a fungicide if anthracnose, rosette, or rust has been a problem in the past. Myclobutanil and sulfur are not effective against anthracnose.
Cover sprays: every 2 weeks postbloomJapanese beetleAcetamiprid or carbarylApply as needed.
Bloom: appearance of berry color to harvest2Spotted wing drosophilaMalathion, acetamiprid, or spinosadMalathion rarely induces secondary pest populations. Use malathion in rotation with acetamiprid and spinosad.

1Insecticides and fungicides can be mixed in the same tank and sprayed together.

2Refer to product labels for preharvest interval (PHI) or the number of days between final spray and harvest.

Bunch Grape

Most grape plantings, except muscadine, require a preventive schedule of fungicide and insecticide sprays for successful production. Pests such as black rot can completely destroy a crop of fruit. However, the following sanitation and cultural practices will reduce the need for pesticides.

  • Keep vines well pruned according to recommended standards. This prevents overgrowth of vines and a dense canopy. It also removes insect-infested wood. Pruning improves air circulation and sunlight penetration, thus promoting rapid drying after rains and dew. Penetration of sprays into a foliar canopy also is better when vines are pruned.
  • Remove and destroy mummified fruit (shriveled, dry, raisin-like) on vines as well as fruit on the ground. Fruit rot organisms of grapes can survive through the winter on old vines and dried fruit on the vines and ground.
  • Prune and destroy vines with stem cankers as they are also a site for fungi to survive through the winter.

Table 1.5. Disease and Insect Management for Home Orchards—Bunch Grape

Time of ApplicationPest ControlledMaterial to Use1Comments
Dormant seasonEuropean red mite, mealy bug, scaleHorticultural oilMake two applications of horticultural oil during the dormant season.
Delayed dormant: when buds swellMealy bugMalathion
New growth sprays: when new growth reaches 2–4 inches long and again 7–10 days laterBlack rot, Phomopsis, powdery mildew, downy mildewCaptan or mancozeb
Prebloom: just before blooms openBlack rot, Phomopsis, powdery mildew, downy mildewCaptan, mancozeb, or myclobutanilMancozeb and myclobutanil are most effective against black rot.
Prebloom: just before blooms openMalathion
BloomBlack rot, powdery mildew, downy mildewCaptan or myclobutanil
Postbloom: when most bloom caps have fallenBlack rot, powdery mildew, downy mildewCaptan or myclobutanil
Postbloom: when most bloom caps have fallenLeaffooted bug, stinkbug, Japanese beetle, grape berry moth, grape curculio, rose chaferMalathion or carbaryl
Summer cover spraysJapanese beetle, green June beetle, grape berry moth, grape curculioMalathion or carbaryl
Preharvest sprays2Green June beetle, Spotted wing drosophila, wasp, yellow jacketMalathion or carbaryl

1Insecticides and fungicides can be mixed in the same tank and sprayed together.

2Refer to product labels for preharvest interval (PHI) or the number of days between final spray and harvest.

Strawberry

Strawberry plants often can be grown almost disease-free without spraying. Weather conditions, however, can cause diseases to develop and spread, and spraying will be necessary. The following practices will improve the effectiveness of the pesticides and may lessen the need for sprays.

  • Practice dormant season sanitation. This can reduce disease pressure most years. Strawberry leaf spots and botrytis blight pathogens can survive through the winter on old leaves and debris on the bed. Clipping old leaves, raking, and composting or destroying will help with disease control.
  • Control weeds during the growing season. Weeds increase disease by reducing light penetration and air circulation, and they intercept pesticide sprays. Weeds also can harbor insects and mite problems.
  • Spotted wing drosophila (SWD) is a serious, invasive pest that infests developing fruit. To reduce the population of SWD, remove fruit that has fallen to the ground as well as fruit on plants that is diseased or damaged.
  • Alternate insecticides so that SWD does not build resistance to insecticides.

Table 1.6. Disease and Insect Management for Home Orchards—Strawberry

Time of ApplicationPest ControlledMaterial to Use1Comments
Plant establishment to dormant Spider miteHorticultural oil or insecticidal soap
PrebloomCrown borer, strawberry weevil, leafroller, insects that cause cat-facing, snail, slug, strawberry clipperCarbaryl or malathion
BloomGray mold, anthracnoseCaptan
Postbloom to harvest2Gray mold, anthracnose,Captan
Postbloom to harvest2aphid, tarnished plant bug, spider mite, whitefly, spotted wing drosophilaMalathion or carbaryl; use insecticidal soaps for spider mites

1Insecticides and fungicides can be mixed in the same tank and sprayed together.

2Refer to product labels for preharvest interval (PHI) or the number of days between final spray and harvest.

Table 2. Products Available in Small Packages for Disease Control in Home Fruit Crops

Active IngredientProduct Name
AcetamipridOrtho Flower, Fruit & Vegetable Insect Killer
Boscalid + pyraclostrobin + lambda cyhalothrinBonide Fruit Tree & Plant Guard
CaptanHi-Yield Captan Fungicide, Bonide Captan Fruit and Ornamental, Southern Ag Captan Fungicide
CarbarylFerti-lome Broad Spectrum Lawn and Garden Fungicide; Bonide Fung-onil Concentrate; Monterey Fruit Tree, Vegetable, and Ornamental Fungicide; Ortho Garden Disease Control; Hi-Yield Vegetable, Flower, Fruit, and Ornamental Fungicide
Copper fungicidesConcern Copper Soap Fungicide; Hi-Yield Copper Fungicide; Bonide Copper Liquid Concentrate; Monterey Liqui-Cop; Southern Ag Liquid Copper Fungicide; Fertilome Natural Guard Copper Soap Liquid Fungicide
Horticultural oilBonide All Seasons Horticultural Spray Oil, Ferti-lome Horticultural Oil Spray, Monterey Horticultural Oil, Southern Ag Parafine Horticultural Oil
MalathionBonide Malathion Insect Control, Hi-Yield 55% Malathion Insect Spray, Ortho Max Malathion Insect Spray, Spectracide Malathion Insect Spray, Southern Ag Malathion 50% EC
MancozebBonide Mancozeb Flowable with Zinc
MyclobutanilSpectricide Immunox Multipurpose Fungicide, Ferti-lome F Stop Lawn & Garden Fungicide, Monterey Fungi-Max
PermethrinBonide Eight Insect Control Vegetable Fruit & Flower, Hi-Yield Indoor/Outdoor Broad Use Insecticide
PropiconazoleBonide Infuse Systemic Disease Control
PyrethrinsPyGanic Gardening
SpinosadSouthern Ag Conserve Naturalyte Insect Control; Bonide Captain Jack’s Dead Bug Brew; Ferti-lome Borer, Bagworm & Leafminer Spray; Monterey Garden Insect Spray
StreptomycinFerti-lome Fire Blight Spray
SulfurBonide Sulfur Plant Fungicide; Ferti-lome Dusting Sulfur (also usable as wettable spray); Hi-Yield Wettable Dusting Sulfur (also usable as wettable spray); Safer Brand Garden Fungicide; Southern Ag Wettable or Dusting Sulfur

 

Download a PDF of Home Orchards Disease and Insect Control Recommendations, IPM-1308.

 

Use pesticides only according to the directions on the label. Follow all directions, precautions, and restrictions that are listed. Do not use pesticides on plants that are not listed on the label.

The pesticide rates in this publication are recommended only if they are registered with the Environmental Protection Agency or the Alabama Department of Agriculture and Industries. If a registration is changed or canceled, the rate listed here is no longer recommended. Before you apply any pesticide, check with your county Extension agent for the latest information.

Trade and brand names used in this publication are given for information purposes only. No guarantee, endorsement, or discrimination among comparable products is intended or implied by the Alabama Cooperative Extension System.

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