Southwest - Spring 2022

Stuart Gauthier, Singh, Raghuwinder, Strahan, Ronald E., Fontenot, Kathryn, Kirk-Ballard, Heather

LSU AgCenter Horticulture Hints for Southwest Louisiana Spring 2022 header.

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Home Fruit Orchard


Citrus trees require annual fertilization for good growth and high yields of good size, high quality fruit. Newly set trees should not be fertilized until they show signs of growth, usually six weeks after they are set in the spring, usually in mid-March. On newly planted trees, apply half a pound of 8-8-8 or 13-13-13 per tree in mid-March.

After the second year, fertilize citrus trees in February. Apply 1 to 1 ½ pounds of 8-8-8 or 13-13-13 per year of tree age up to 12 years. Increase the rate of fertilizer 1 to 1 ½ pound per year as the tree gets older. A 1-year-old tree gets 1 to 1 ½ pounds of 8-8-8 or 13-13-13, and a 5-year-old tree gets from 5 to 7 ½ pounds. The fertilizer rate is increased each year until the tree is 12 years old. Trees 12 years old and older are at the top limit of fertilizer and should receive 12 to 18 pounds of 8-8-8 or 13-13-13 per tree. A simple fact to remember is that 1 pint of 13-13-13 weighs about 1 pound and a quart weighs 2 pounds. (Example: A 1-year-old tree will require 1 pound or 1pint of 13-13-13, and a 4-year-old tree will require 4 to 6 pounds or 2 to 3 quarts of 13-13-13.)

A small amount of nitrogen fertilizer (one-quarter pound of ammonium nitrate or ammonium sulfate per year for the age of tree or one-half pound of calcium nitrate per year for the age of the tree) should be applied to bearing trees (trees 4 years and older) in late May or early June. The rate of fertilizer is increased each year until the tree is 12 years old. This helps the tree make adequate vegetative growth and appropriately sized fruit. The additional nitrogen also will encourage the tree to set a crop the following year.

Nitrogen fertilizer should not be applied after the end of June. Fertilizer applied after the end of June will decrease cold hardiness and delay fruit from ripening. Broadcast the fertilizer beyond the spread of the limbs where most of the feeder roots occur.

A general rule when fertilizing trees is to put your left shoulder near the outer branches and hold the can of fertilizer in your right hand. You can simply walk around the tree and evenly spread the fertilizer in a 12- to 18-inch band on the outer branches of the tree. This technique will ensure that the fertilizer is placed a safe distance from the tree.

Avoid fertilizing citrus trees after the end of June. Late fertilization will encourage vigorous growth, delay fruit maturity and decrease the cold hardiness of the tree. Homeowners are also encouraged to pay strict attention to the amounts of fertilizer applied to citrus trees.

Amounts above those recommended will encourage vigorous growth, delay fruit maturity, ruin fruit quality and decrease cold hardiness. Vigorous growth can result in extensive freeze damage or death of the trees, even in a moderate freeze.

Stuart Gauthier
Extension Agent

Prune Crape Myrtles Properly


An appropriate time to prune most summer-flowering trees and shrubs, including crape myrtles, is late January through early March.

Crape myrtles are leafless at this time, and it is easy to see the structure of the tree. This is helpful when deciding where to prune. Pruning generally should be done to enhance a crape myrtle’s natural shape while also correcting any problems.

An unfortunate trend in crape myrtle pruning is to cut back the tops, which results in a tree reduced to large main branches ending in stubs. The lush growth that occurs at these cut sites appears vigorous but actually is structurally weak and more susceptible to fungal diseases, such as powdery mildew. Even more, when pruning is conducted improperly over the years, unsightly large, swollen knobs form at the points where pruning is done each year. Although cutting a tree back can be considered an option when pruning crape myrtles, it is certainly not, and never has been, the preferred way of handling these graceful and beautiful trees. Perfectly beautiful crape myrtles often are disfigured and deformed for no good reason. In most cases, this annual pruning is needless work and expense that generates huge amounts of pruning trash that ends up in landfills. Also, it is not healthful for the trees in the long run.

To prune a crape myrtle properly, first decide if it needs to be pruned. As with any pruning project, you must have a specific and valid purpose in mind before you begin. In other words, if you can’t come up with a good reason to prune your tree, leave it alone.

If you see something that calls for pruning, however, study the tree carefully and determine what needs to be pruned to accomplish the specific purpose identified. If the problem is one branch touching the edge of the roof, deal with that branch. Don’t cut back the whole tree.

Every crape myrtle will need some pruning in its life to grow properly and fit well with its surroundings. Here are some examples:

  • Over time, branches that are too low on the trunk will need to be pruned to raise the canopy to the desired height. We often need to remove weak, thin or vertical shoots from the inner part of the tree to produce a cleaner looking tree.
  • Selected branches may need to be pruned back to a side branch or the trunk to create a shapelier tree and to eliminate crossed and rubbing branches. Generally, avoid cutting back or shortening branches much larger than your finger. However, cutting larger branches back to a side branch or to the trunk when needed is fine.
  • Prune to keep suckers removed from the base of the trunk. This is especially important in younger trees.
  • You also may need to redirect the direction of a branch’s growth. This can be done by studying the branch carefully and looking for a side branch that grows in the desired direction. Prune back to that branch and you have redirected the growth of the branch. This can be helpful where trees are too close to a structure, such as a house. A common problem is crape myrtle trees being planted too close to a house. Always locate trees at least 10 feet away from the house roofline. In situations where trees are close to a house and branches are hitting the roof, branches can be redirected to grow away from or up and over the roofline by using this pruning technique.

Stuart Gauthier
Extension Agent

A small circular planter with two types of plants. One is a trailing, cascading vine. The other is a plant with bright purple flowers located in the center of the pot.

Get Creative With a Colorful Container Garden


You don’t need a large yard or a lot of space to create a beautiful garden. You can create beautiful planters or containers that fit any space with limitless plant combinations that bring beauty and joy to wherever you call home.

There are plenty of options to choose from when it comes to the size, shape and color of containers and planters — hanging baskets, window boxes, small and large containers for combination plantings, single plant containers and clusters of pots. Your options for the plants themselves are plentiful and diverse, too.

To create a beautiful container design, begin by choosing a container that suits your spatial needs. Most garden centers, retail nurseries and online shopping venues offer many types.

Next, choose the plants and arrange them in a design of your choosing. Keep them looking good until you want to change the design.

One of the great advantages is that you can change these out. Year after year, you can play with the plant combinations, colors, textures and themes.

A combination planter typically has what is known as a filler, a thriller and a spiller. If you haven’t heard these terms yet, let me explain them to you.

The thriller is the plant that is main attraction of your container planting. It will be the focal point of your design. Choose a plant that has some height and a striking flower form or color.

The filler is just as the name suggests. Use these plants to fill in areas to create a fuller look in the arrangement. Fillers are medium-sized plants, typically in a mounded form, that make up the bulk of the plant material in the container. You can choose just one type of plant for focal impact, or you can choose several different plant types of similar sizes.

Spiller plants are the trailing, cascading plants that flow over the sides of the containers and complete the arrangement.

When choosing fillers and spillers, a good rule of thumb is to use an odd number of plants — three, five, and seven and so on.

Symmetry brings a good balance to beginning designs. Although it is not required to have an equal number of similar or identical plants on each side of the focal point, it does bring a visual balance to the arrangement.

Be sure you bring different textures into the container planting and design. Add fine-, medium- and coarse-leaved plants. Use tall pieces that bring height for the focal point; shorter, mounding species en masse; and low-growing spiller plants to soften the edges of the container planting.

Lastly, use proportional sizes to match the container. For large containers, use larger plants; use smaller plants in small containers. The rule of thumb is that the tallest plant should not be taller than 1 to 2 times the height of the container.

Now is the fun part: picking the plants. Be sure that you use season-appropriate plants. For example, if you are creating a design for the summer, make sure you are using heat-tolerant, warm-season annuals and perennials.

Most trees and shrubs will be fine throughout the seasons, but be sure to use evergreen selections unless you plan to rotate them out with the seasons as you do with your annuals and perennials.

A metal rectangular planter planted with a variety of plants.
You can use interesting container for an artistic flair.
A large planter filled with ornamental kale and violas are the outside of the planter and yellow and purple flowering types of snapdragons in the center.
Ornamental kale snapdragons and sorbet violas make a dazzling container plant display.

Here are a few suggestions of Louisiana Super Plants for each category for medium-sized containers.

Thriller plants: Suncredible yellow sunflower, Flamethrower coleus series, Fireworks pennisetum, Senorita Rosalita cleome, Intenz Classic celosia, Flutterby Tutti Frutti buddleia, Camelot foxglove series, Diamonds Blue delphinium, Jolt and Amazon dianthus series.

Filler plants: Beacon impatiens series, Babywing begonia series, Serena and Serenita Raspberry angelonia, Mesa gaillardia series, Butterfly and Lucky Star pentas series, Sorbet viola series, compact varieties in the Sunpatiens impatiens series, Kauai torenia series.

Spiller plants: Mini Vista Indigo and Vista Bubblegum in the Supertunia petunia series, Homestead Purple verbena, lemon sedum.

Heather Kirk-Ballard, Ph.D.
Consumer Horticulture Specialist

Checklist for March, April, May


A basket full of purple egg plants with white verigation.
Eggplants.

March

  1. In the vegetable garden: Work compost and a preplant complete fertilizer, such as 13-13-13, at seven to 21 days before planting or laying mulch cloth. In south Louisiana plant beans, cantaloupes, collard greens, sweet corn, eggplants, herbs, mustard greens, okra, Southern peas, peppers, pumpkins, summer squash, tomatoes and watermelons. North Louisiana should wait until the beginning of April.
  2. In the lawn: Make your first mowing at a low setting and remove grass clippings. Continue to treat cool-season annual weeds in the lawn. Let your lawns begin to green up before you start fertilizing lawns this month after March 15 in south Louisiana and after April 1 for north Louisiana.
  3. In the landscape beds: Continue to enjoy your cool-season bedding plants that were planted in fall. They will have another outstanding display of color this early spring before it is time to replace them with warm-season bedding plants around the beginning of May.
  4. Trees and shrubs: Spring is a great time to plant new trees and shrubs. Consider size, fall foliage change, flower interests and whether you want evergreen or deciduous trees or shrubs when selecting new plants. Apply dormant oils to control scales, whiteflies and other sucking insects on trees and shrubs that may be affected. Fertilize this month if you missed it in February. Begin your preventative rose spray program in early March. Alternate fungicides to control blackspot and powdery mildew. Treat in the early morning or late evening every week. Copper is a great organic alternative to other traditional fungicides.
  5. Fruit: Apply fertilizer to fruiting trees that were not fertilized in winter now at the recommended rate. Recommended 8-8-8 fertilizer rates:
    • Blackberry – Half of a pound per plant.
    • Blueberry – Fertilize with 2 ounces per year of growth up to 1 ½ pounds.
    • Fig – 1 pound per year of 8-8-8 up to 10 pounds.
    • Citrus, peaches and plums – 1 to 1 ½ pounds per year of tree age up to a maximum of 8 pounds.
A flowerbed with tall, heat-shaped, white and green veriegated caladiums standing over some short dark green and purplish ornamental plants.
Caladiums.

April

  1. In the vegetable garden: Apply pine straw mulch to prevent weeds in the vegetable garden. The last week of April is a good time to side-dress vegetables planted in late March with ammonium nitrate, ammonium sulfate, calcium nitrate or potassium nitrate. Be sure to apply several inches away from the base of the plant and water in immediately to prevent burning. Stake tomatoes when the first flower clusters to prevent fruit from touching the ground and to help prevent fruit rot.
  2. In the lawn: Fungal diseases are common this time of year. Keep an eye out for large patch and gray leaf spot. St. Augustinegrass is susceptible and centipedegrass is more resistant. Use fungicides containing maneb, myclobutanil, PCNB, propiconazole, thiophanatemethy or triadimefon every 10 days as the fungus persists. Control cool-season annual weeds, such as bedstraw, chickweed and henbit, from producing seeds that will be a headache next winter if not taken care of now
  3. In the landscape beds: You can begin planting warm-season annuals, perennials and caladium bulbs this month. Thin border plants and clumping ground covers, such as monkey grass, liriope and hostas, this month. Use a 2-inch mulch layer on newly planted landscape beds to conserve moisture and to control weeds.
  4. Trees and shrubs: Prune spring-flowering shrubs, such as azaleas, camellias, viburnum and spireas, after they have finished flowering. Fertilize after pruning. Powdery mildew can be a problem on the foliage of ornamentals. Control with fungicides containing one of the following active ingredients: azoxystrobin, copper sulfate, myclobutanil, trifloxystrobin or triforine.
  5. Fruit: Thin fruit on your fruit trees this month. Thinning fruit improves the size and quality of the remaining fruit and can help reduce the spread of diseases.
Several limbs in covered in long dark leaves and bunches of light orange loquat fruits.
Loquats.

May

  1. In the vegetable garden: Now is a critical time to scout vegetable plants for immature stink bugs and leaf-footed bugs. If you see them spray soon. When they turn into adults, they are much more difficult to control. Continue to plant warm-season vegetables.
  2. In the lawn: Be on the lookout for weeds. If weeds are present, you can apply a lawn weed killer labeled for use on your lawn. Early weed control before going into hot summer months is essential for the best turfgrass vigor. If your weeds are under control, you can encourage vigorous turfgrass growth by aerifying your lawn. Plug removal is the best method to provide air to roots. If you fertilized in March, you may go ahead and fertilize again late this month. Lay sod or sprig your lawn this month and throughout the summer, if needed. Trees and shrubs: Mulch trees. Prune ever-blooming roses back by one-third of their height to encourage a vigorous fall bloom.
  3. In the landscape beds: Watering can be laborious in extended droughts in summertime. Consider installing a microirrigation system. Home installation kits and timers are homeowner friendly and readily available online and in stores. Be sure to buy a timer with a rain delay for days with rain. Next month is National Pollinator Month. Plant perennials, such as coreopsis, daylily, Echinacea, gaillardia, gerbera daisy, gaura, milkweeds, Louisiana phlox, passion vine, cardinal flower, sunflowers, bee balm, Mexican sage, verbena, rudbeckia, coral honeysuckle, rose mallow and irises.
  4. Trees and shrubs: This is a good time to prune spring-blooming shrubs now through no later than July to encourage new growth. Be careful not to prune summer-blooming shrubs, such as hydrangeas, butterfly bush and crape myrtles. Azalea lacebugs can be a problem in late spring and into summer. Look for white mottling or spots on the tops of leaves and dark brown insects on the undersides of leaves. Use acephate or malathion to control and be sure to cover the undersides of leaves to control the insects that are found there.
  5. Fruits: Bird netting may be necessary for fruit trees and shrubs this month. It is harvesting time for mayhaws, loquat, mulberry, peach, sweet orange, blackberries and blueberries this month.

Heather Kirk-Ballard, Ph.D.
Consumer Horticulture Specialist

Spring Vegetable Tips


If there is ever a time to be outside in Louisiana, it’s in the short-lived spring season we get. I recommend getting into the vegetable garden as early as possible. January and February are wet and cold. As soon as that garden dries in March, get going before it gets hot. The heat will come in a week, a month or, if we are lucky, in two months … in Louisiana you never know.
Two wood framed, triangular garden beds surrounded by pea gravel and filled with young snap bean and tomato plants.
Snap beans and tomatoes.

Steps to success

  1. Remove weeds and insect- and disease-infested plants from the fall garden.
  2. Work the soil. Loosely till or spade your garden area.
  3. Apply fertilizer or aged manures. A key to achieving heavy vegetable harvests is using adequate fertilizer. For example, most mixed gardens (all warm-season crops combined into one area) require a medium rate of fertilizer. There are hundreds of fertilizers to choose from. To keep the recommendation simple, I would apply one-half pound to 1 pound of 13-13-13 for every 10 linear feet of row in your garden space. That rate is assuming your rows are no wider that 48 inches. That is about 1 to 2 cups of 13-13-13.
  4. Water that fertilizer in!
  5. Plant!!! In south Louisiana plant in early-to-mid-March. In central and northern Louisiana plant April 1 or in late March if we are warm.
  6. Water your newly planted seeds and plants within one hour of planting. Keep the ground moist, not saturated, throughout the life of the garden.
A closeup of a pale yellow okra flower with dark purple center growing on stalk next to an okra pod.
Okra flower and pod.

Vegetables to Plant in March

Direct-plant snap beans, Swiss chard, radish, lettuce, collards, mustards, turnips, cabbage, broccoli and sweet corn seeds. Plant tomatoes, peppers and eggplant transplants. Plant cantaloupes, squash, cucumbers and watermelons well after danger of frost is over. This is usually after March 15 in south Louisiana and closer to April 1 in north Louisiana.

... and in April

Plant snap beans, butter beans, radishes, collards, cucumbers, eggplants, cantaloupes, okra, Southern peas (field peas), peanuts, pumpkins, winter squash, summer squash, sweet corn, sweet potatoes (late April), tomatoes (transplants), peppers (transplants) and watermelons.

... and in May

Most spring vegetables can be planted in May, since the soil has warmed and danger of frost has passed. Plant sweet potatoes (transplants), heat-tolerant tomatoes (Sun Master, Sun leaper, Florida 91, Phoenix, Bella Rosa, for example), okra, Southern peas, pumpkins, peanuts, sweet corn, watermelons, cucumbers, butter beans, squash, cantaloupe, collards and eggplants (transplants). Snap beans, butter beans, sweet corn, tomatoes (except heat-tolerant varieties) and peppers (transplants) should be planted in the early days of May to prevent poor fruit set because of high temperatures.

Enjoy the Garden,

Kathryn “Kiki” Fontenot, Ph.D.
Vegetable Gardening Specialist

Lawn Weed Control


Herbicides can be effective tools for reducing weeds in your yard, but the best way to manage weeds is to grow a thick, healthy lawn. Lawns that are managed properly are lush and healthy, with few weed problems.
A short, wide growing plant called blue eyed grass growing in turfgrass.
Blue eyed grass is an iris that often infests lawns in the early spring.
A plant with three lobed leaves with red fruit growing in turfgrass. There are pine needles scattered over the top of the weed.
Indian mock strawberry infests thin lawns.
Close up of a small plant emerging from the soil. A dime is put next to the seedling to show scale.
Crabgrass emerges in early February in south Lousiana.
A large patch of weeds called spotted burclover growing in turfgrass. Each leaf has three lobes with brown spots on a green leaf.
Spotted burclover is a common weed seen early in the spring.

Pre-emergence herbicides

Weed preventer or pre-emergence herbicides can be helpful in preventing the emergence of several summer annual grasses and broadleaf weeds. Pre-emergence herbicides may be applied safely in late winter to early spring to all established southern lawns. Most pre-emergence products for home lawns are granular and should be applied with drop or broadcast spreaders and “watered in” soon after application. These types of herbicides kill weeds as they germinate, so application timing is extremely important. You must apply before the weeds, such as crabgrass, germinate. Also, these pre-emergence herbicides that you are applying to prevent summer weeds will not kill any existing winter weeds. Residents in the New Orleans area and southernmost areas of the state should apply pre-emergence herbicides in late January or early February and then follow up with another application in mid-April. From Alexandria to Baton Rouge, residents should apply around Feb. 10, with a follow-up application in late April. If you live in north Louisiana, try to get these herbicides applied in late February, with a follow-up application by early May. Some pre-emergence herbicide trade names to look for are Scotts Halts, Barricade and Hi-Yield Crabgrass Preventer with Dimension. Consult product labels concerning rates and application techniques. When it comes to the successful use of pre-emergence herbicides, going a little early with your applications is better than applying too late. Winters over the last few years have been nearly nonexistent. Lack of cold weather has caused an earlier emergence of summer weeds. Let’s get those pre-emergence herbicides out on time.

Post-emergence herbicides

Post-emergence herbicides are used to kill weeds that already have emerged in the lawn. Winter broadleaf weeds usually are prevalent in the late winter to early spring throughout the state. MSM Turf (metsulfuron) and Celsius (theincarbazone-methyl + dicamba + iodosulfuron) are two highly effective broadleaf killing herbicides that have consistently performed well in LSU AgCenter evaluations on winter broadleaves. MSM is effective on wild onion, false garlic and blue-eyed grass (an iris), as well as most winter broadleaves. These are low-use-rate herbicides, especially MSM. Follow the product labels very carefully so that lawns and trees are not injured. Do not use Celsius on carpetgrass. More widely available broadleaf weed killers include “trimec type” herbicides formulated with the active ingredients 2,4-D; dicamba; and mecoprop. Some examples of trade names to look for with these active ingredients include Trimec Southern, Ortho Weed B Gon for Southern Lawns, and Ferti-lome Weed Free Zone. Product manufacturers will often recommend a follow-up spray two or three weeks after the first application. Broadleaf weed killers such as these are widely available and can be used on most southern grasses. Injury can occur, however, when using them on St. Augustinegrass and centipedegrass as the weather gets warmer in late spring. Atrazine is an herbicide that is effective on winter broadleaves and also controls annual bluegrass, especially when applied before the annual bluegrass flowers. Most garden centers have a good supply of atrazine on their shelves. Weed and feed products labeled for St. Augustinegrass and centipedegrass contain atrazine as their active ingredient. However, liquid atrazine sprayed on weeds in the yard has worked better in LSU AgCenter trials than atrazine weed-and-feed products impregnated on a fertilizer granule.

What about weed-and-feed products?

Weed-and-feed herbicides can be used at the times recommended for the first fertilizer application of the year. Apply weed-and-feed in the New Orleans area from mid-to-late March. For north Louisiana, early-to-mid-April is the time. Just be aware that applying weed-and-feed too early (late February to early March) may encourage outbreaks of large patch disease. Clean your sprayers thoroughly with an ammonia solution if the same sprayer is used for applying insecticides or fungicides on landscape plants. It is best to buy a sprayer specifically dedicated for weed killers, however, to avoid accidental injury to desirable plants. As always, be sure to read and follow product label recommendations before using any pesticide.

Fertilizing the lawn

Lawns vary in the amount of fertilizer required during the growing season. See the table below for information regarding the number and timings of fertilizer applications recommended for lawn species grown in Louisiana. Bermudagrass and St. Augustinegrass require the most fertilizer compared to other lawn grasses. Centipedegrass and zoysia only require one to two applications of fertilizer per year.

Lawn

Number of fertilizer applications/year

Recommended months

Bermudagrass

3

March/April, June, August (optional September)

Centipedegrass

1 to 1.5

April and possibly June at ½ fertilizer rate

St. Augustinegrass

2 to 3

April, June, August

Zoysia

2

April and July


Which fertilizer should I use during the growing season?

A spring application of weed and feed could serve as your first fertilizer application. For future applications during the growing season, consider using 3:1:2 or 4:1:2 ratios of nitrogen, phosphorus and potassium (N-P-K) as a guide for the analysis of fertilizers to choose for the lawn. For example, a fertilizer with an analysis of 21-7-14 is a fertilizer with a 3:1:2 ratio. You would be better off getting your soil tested. Soil tests would be most helpful to determine exactly what nutrients are needed to make your lawn beautiful. Contact your parish extension office concerning soil sampling your yard today.

Ron Strahan, Ph.D.
Weed Scientist and Turfgrass Specialist

Exobasidium Leaf Gall


Leaf gall of camellias and azaleas is a fungal disease favored by extended periods of cool, wet weather during spring. This is primarily a leaf disease, but occasionally it may occur on stems, flowers and seed pods. There are mainly two species of the Exobasidium fungus that cause this disease: Exobasidium vaccinii on azaleas and E. camelliae on camellias. Symptoms of leaf galls start appearing soon after the plants finish flowering. Leaves are distorted and become thickened with a fleshy or leatherlike texture (Figures 1 and 2). Galls tend to be pale green, pink or white (Figure 3) in the beginning, but as they develop, they become white and powdery. The white powder material is spores of the fungus, which readily disperse via air currents and by splashing water. As the galls get older, they shrivel up, dry out and turn brown and hard (Figure 4). Older galls fall to the ground, where they survive and may serve as a source of inoculum for the next spring’s susceptible growth.
A camellia branch with three white galls on the end of the branch.
Figure 1: A leaf gall on a camellia. Photo by Raj Singh.
Three groups of camellia leaves showing varying levels of color. Some are green, pink and brown.
Figure 3: Camellia galls show color variations. Photo by Raj Singh.
Two groups of azalea leaves laying flat on a white table. There are several protruding green galls on the leaves.
Figure 2: A leaf gall on an azalea. Photo by Raj Singh.
Close up of light brown distorted foliage.
Figure 4: An older mature gall turns brown on an azalea. Photo by Raj Singh.
Management of leaf galls is achieved primarily by adopting good cultural practices. Proper pruning and discarding of galled leaves is very important in reducing the spread of the disease. Cut galled leaves a couple of inches below the symptoms. Before discarding them, put them in zippered plastic bags. Remove and destroy affected leaves with galls that have fallen on the ground. Improve air circulation by selective thinning of the canopy of established plantings to promote rapid drying of foliage and maintain adequate spacing when establishing new plantings to avoid creating favorable conditions for disease development. Fungicides may help avoid infection when applied beginning at bud break. Repeated applications may be required every 10 days as long as the conducive weather conditions persist for disease development. For fungicide selection, please consult your local LSU AgCenter extension agent. For more information on leaf galls of azalea and camellia, please contact Raj Singh at 225-578-4562 or email rsingh@agcenter.lsu.edu.

Raj Singh, Ph.D.
Associate Professor
Director, Plant Diagnostic Center

4/21/2022 3:11:30 PM
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