GNO Gardening - April 2019

Christopher Dunaway, Timmerman, Anna, Willis, Joe, Landrum, Derek S.  |  4/23/2019 5:21:02 PM

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4-H on the Move!

By Derek Landrum


The 4-H club at Sherwood Forest Elementary in New Orleans East participated in an overnight camping trip! In late March, this intrepid group of 4-H’ers ventured into the great outdoors at St. Bernard State Park. For many of these campers, it was their first time sleeping outside. With guidance from the 4-H Agents and their club leader, the campers learned how to set-up a tent for camping, how to build a campfire, and how to cook over an open flame. After learning to do so many new things, our campers were ready for dessert, S’MORES! These new campers fell in love with a dessert that up until this trip was only a snack seen on television screens. After some stargazing, it was off to bed for an exciting day in the morning.

After waking to a melody of bird songs and fresh breakfast, the campers learned and practiced wildlife identification and first aid, two important outdoor skills. Prepared with their newfound confidence, the campers embarked on a nature hike before leaving the wonders of nature behind for the comforts of home. Many expressed a profound enjoyment for camping and are looking forward to the next trip.

This 4-H experience was made possible by a generous donation from Emily’s Blooming Youth Fund. If you'd like to help more youth in Orleans Parish experience the outdoors, please consider giving on to Orleans Parish 4-H on GiveNOLA Day, May 7. You can donate at https://www.givenola.org/orleans4H. Want to get hands-on with 4-H? We are always looking for more volunteers, especially for our club leadership teams. Email orleansparish4h@agcenter.lsu.edu for more information.

April Checklist/Garden Tips

  • If you need to prune spring flowering shrubs such as spirea, viburnum, quince, azalea, camellia, jasmine and mock orange, you may do so as soon as they finish flowering. Remember to prune with a specific purpose in mind, and, unless you are trying to create a clipped formal hedge, try to preserve the natural shape of the shrub.
  • Be sure to mulch newly planted beds of shrubs or bedding plants with a two inch layer of leaves, pine straw, pine bark or other materials to control weeds, conserve moisture and keep the soil from packing down.
  • Watch for spider mite damage on many vegetables and ornamentals during dry weather. Very tiny, spider mites are not readily visible to the naked eye. Use a magnifying glass to inspect the plant and look for the tiny red or green eight legged mites. Infested plants get a dull, dusty, unhealthy look to the foliage which eventually turns brown. The spider mites are primarily under the leaves. Spray with a horticultural oil, insecticidal soap, Malathion or Kelthane.
  • After planting bedding plants, water them in with a half- strength solution of your favorite water soluble fertilizer. This gets them off to a good start.
  • Save some of your own seed from your cool season annuals to plant again in your garden this fall. This time of year collect seeds from sweet peas, violas, nicotiana, poppies, calendulas and cosmos. Make sure the seed pods are mature before harvesting.
  • Constant watering rapidly leaches nutrient elements from the soils of container grown plants. To replace them it is best to use either soluble fertilizers or slow release fertilizers. Soluble fertilizers are easy to apply especially when you use a hose end applicator, but they must be applied every two weeks to maintain a constant supply of nutrients. Slow release fertilizers provide nutrients over several months from one application and so cut down on labor.
  • If crape myrtle aphids have been a problem on your trees in the past, treat this month with Bayer Advanced Tree and Shrub Insect Control with Merit. This is applied as a drench to the base of the trees and is absorbed by the roots. The insecticide travels through the tree’s circulatory system up into the foliage making it toxic to the aphids. One treatment protects the tree all summer, preventing aphids and the unsightly black sooty mold they cause.
  • Spray crape myrtles with mancozeb , chlorothalonil or other labeled fungicides to control serious infections of powdery mildew. Powdery mildew appears as a white, powdery material on the leaves. Unlike many fungus diseases that are worse when weather is rainy, this disease is favored by humid, warm weather without rain. It is also occurs on a variety of other landscape plants such as dogwood, euonymus, gerbera daisy, rose and hydrangea, to name a few.
  • Oak trees infested with buck moth caterpillars should be sprayed before the caterpillars begin to migrate down the trunk. Contact local tree care companies to get your trees sprayed.
  • Aphids are a real problem on roses and many other plants in spring. Control with insecticidal soap, oil spray, Malathion or Acephate.
  • As much as is practical, continue to deadhead or remove faded, dead flowers from cool season bedding plants such as pansy, snapdragon and dianthus to promote extended flowering.
  • Spray peach trees regularly with a commercial home orchard or fruit tree spray to prevent plum curculio insects from causing wormy fruit.
  • When buying pesticides, ask for a recommendation for the least toxic material that will do the job and buy the smallest container available. Large sized containers take years to use up and by then the pesticide has often lost its effectiveness.
  • Keep your Louisiana irises well watered now while they flower and through mid summer. Remove any developing seed pods after flowering is finished.
  • Small birds called sapsuckers peck holes in neat rows. The holes just penetrate the bark and cause sap to bleed from them. Later, the sapsuckers return to feed on the sugary sap and any insects that may have been attracted to it. The damage is usually minor, and control is generally not necessary or practical.
  • Cool season herbs and those that thrive during mild weather, such as parsley, dill, tarragon, thyme, sage, cilantro, borage, lavender, chamomile, chervil and arugula, are at their peak this month. They will begin to decline toward late May and finish in early June, so harvest them generously over the next six to eight weeks. Extra harvest can be dried or frozen for use during the summer.
  • Do not delay planting many of the warm season vegetables beyond the middle part of this month. Tomatoes, snap beans, lima beans and bell peppers all set fruit poorly when temperatures are hot. Squashes and corn are both far more likely to have major insect and disease problems when planted later.
  • Pay careful attention to thoroughly watering newly planted trees, shrubs, bedding plants, ground covers and lawns during dry spring weather. Continue watering about twice a week until there is significant rainfall.
  • Tomatoes are staked to keep the plants from sprawling on the ground where the fruit would be more likely to rot. Wait for the first cluster of flowers to appear, and place the stake on the opposite side of the plant’s stem. All of the flower clusters will grow from the same side of the stem, and this will keep developing fruit from getting caught between the stake and the stem.

Common Compost Problems and How to Fix Them

By Anna Timmerman


Composting is becoming increasingly popular with home gardeners, both as a way to reduce household food waste and create healthy garden soil. Compost feeds soil microorganisms, improves soil structure, and adds trace amounts of nutrients to the soil. The compost pile can be anything from a simple mound of material or a fancy tumbler system. Home composting systems usually have to fit into urban or suburban settings without causing issues with odors and pests. In a truly balanced, regularly turned, well-built pile these issues don’t come up as much. The LSU AgCenter has a guide called Troubleshooting Your Compost Pile that is among my favorite publications. This handy table will help to keep the compost pile from becoming a nuisance.

Regardless of size, composting is easy as long as the nitrogen to carbon ratio is roughly one part nitrogen (green grass clippings, food waste, and other wet material) to thirty parts carbon (dry leaves, shredded paper, cardboard, wood materials). For more information on composting systems, click here. Never add greasy food scraps, meat, or dairy products to the pile, as this can attract rodents and other critters to your yard. Citrus rinds don’t metabolize quickly so many people do not compost them, but eventually they break down.

A good system for keeping odors and fruit flies out of the kitchen is to collect kitchen waste in a sealed container. There are several nice countertop compost collector receptacles on the market that are airtight and blend in with other kitchenware. A sealed plastic container or gallon bag can also work great, especially if you freeze food waste before taking it outdoors and adding it to the pile. Freezing food scraps keeps them from rotting in the kitchen and eliminates the fruit fly issue. When your container is full, simply add the frozen scraps to the pile and incorporate. Keep bags of leaves, shredded paper, and cardboard on hand to add as needed, keeping the carbon and nitrogen balanced.

Keeping the odor of the pile in check often involves mixing food scraps into the carbon-rich materials of the pile. If the pile is too wet from frequent rainfall, this too can cause a sulfurous odor. The site of the compost pile should not collect rainwater, building the pile up on a slab or raised area can help to drain excess rain out quickly. Anaerobic conditions can also cause a rotting smell. Flipping the pile every week or two can help to add oxygen back in, which is in turn used by soil microorganisms. If these microorganisms thrive, food waste gets broken down quicker, before it has a chance to ferment and release odors.

Inversely, if the pile is too dry, materials will not break down and those workhorse microorganisms will search for moister pastures. If nothing seems to be rotting, this is likely the issue. You may need to water the pile during dry spells, this encourages activity and gets the pile breaking down correctly. Shred cardboard and yard waste into smaller, more digestible pieces before adding them in and wetting them down. Large branches, logs and other woody yard waste should be run through a chipper or shredding machine before being added in.

White, moldy growth should be no cause for alarm, soil fungi help to break many compost materials down. The white filaments that appear in compost piles are mycorrhizae, spreading out and metabolizing materials in the pile. When the moisture of the pile is right, you should see a lot of this white, thread-like growth happening. Other types of fungi and mushrooms may appear, this is only helping things to break down into usable compost.

Flies, rodents and other wildlife shouldn’t be hovering around the pile like it is a free all-you-can-eat buffet. If you notice lots of flies, you may have added too many food scraps into the mix all at once. Add browner, carbon-rich materials and flip the pile. Flies breed in rotting food scraps and manure, so try to discourage this by adding a little bit at a time rather than large amounts all at once. Meaty or greasy food scraps are more likely to attract raccoons, opossums, and rats to the area as well. It is best to not add these to the pile.

When the compost system is working correctly, the internal temperature of the pile should be in the range of 90-140 degrees Fahrenheit. If the pile is too small, there may not be enough material available for microorganisms to digest, which ultimately creates this heat. A hot pile is a sign of activity and that the system is working. At temperatures below 90 degrees, not enough is happening to efficiently produce compost. At temperatures above 140 degrees, microorganisms either die off or move to more favorable environments.

Gardeners shouldn’t rely completely on compost to supply all of the nutrients needed by the garden, but adding a few inches yearly can significantly boost garden performance. Most compost has a nitrogen, phosphorus, and potassium (N-P-K) ratio of between 1.5-0.5-1 to about 3.5-1-2. By comparison, most garden fertilizer products fall in the 5-5-5 to 13-13-13 range, so be forewarned. If you are growing fruits and vegetables or even heavy-feeding annual flowers, you’ll need to add other things along with the compost you produce to keep things going. To figure out exactly what to add, do a soil test (LSU soil testing lab info here).

While composting isn’t rocket science, there are some pitfalls that can arise along the way. Monitoring your pile from time to time and adding the right mix of things to it can help prevent many of these issues from happening. Make compost pile maintenance a part of your weekend yard work routine. We should all do our part to keep yard waste and food scraps out of the waste stream. Compost is a wonderful, free product that gardeners should embrace and produce right in their own landscape, without it becoming a nuisance. For additional compost resources, please visit www.lsuagcenter.com.

Geaux Grow Natives!

By Linda Barber-Auld "BugLady"


I'll never forget the first time I met author Doug Tallamy on the evening of October 10, 2013 at his lecture at Longue Vue Gardens. I purchased his book, "Bringing Nature Home-- How You Can Sustain Wildlife with Native Plants" and asked him to sign it. Along with his signature, he wrote these words: "Garden as if life depended on it!"

Doug's words inspired me to learn more about native plants and to try them in my landscapes. I loved them from the start. In early 2014, I saw Monarch Watch's report on the lowest Monarch butterfly overwintering population in recorded history. That shocked me into focusing my efforts to help Monarchs. Trying different approaches and collaborations to raise public awareness about Monarchs and propose solutions, my various projects have educated and inspired many folks to join the native plants bandwagon. This year, in 2019, aware of the latest scientific reports of general biological decline, I want more than ever to make a positive impact in my community.

Over the past 42 years Louisiana and Mississippi trails have been my playground and my classroom. Performing butterfly surveys for the North American Butterfly Association, I have seen firsthand which plants best attract winged beauties. Propagating native plants in my own gardens has shown me the connection between plants and their various insect communities. By raising over a hundred different species of butterflies and moths on native plants, and closely observing bees, wasps and other beneficial insects, I've arrived a deep appreciation of how these creatures recognize native plants as their "real food" and thrive on them. To spread the joy of my experience is why my 2019 project for the Greater New Orleans and Baton Rouge communities is titled Geaux Grow Natives.

The concept of "If you plant it, they will come" really does work! The Geaux Grow Natives mission is to make twelve wonderful Louisiana native plants available to the gardening public. Each plant provides important support for beneficial insects that need it. Each one has repeatedly proven to attract butterflies and other beneficial pollinators. Some plants are caterpillar hosts, some are nectar producers and many are both. Five local area plant nurseries and the New Orleans Master Gardeners have signed on to propagating these plants. Fourteen locations have agreed to make them available for public purchase, starting May 4, 2019.

Seven plants will be offered for the Spring 2019 planting season and seven more for Fall (the two Spring milkweeds are repeated). I will conduct a free workshop on growing and caring for these special natives at each retail location on the following schedule:


Spring Tour Dates:

May 4
Jefferson Feed - Jefferson 9 - 11:30 am
Double M Feed 12:30 - 3:00 pm

May 11
Harold's Plants 9 - 11:30 am
Options 1:30 - 3:30 pm

May 18
Longue Vue Gardens 10 am - Noon
Charvet's 1:30 - 3:30 pm

May 25
Clegg's - Siegen lane 9:30 am - 12 Noon
Clegg's- Denham Springs 1 - 3 pm

June 15
Pelican Greenhouse Plant Sale 9 am - Noon
Fall Tour Dates:

Sept. 7
Jefferson Feed 9 am - 11:30 am
Double M Feed 12:30 - 3 pm

Sept. 14
Crosby Arboretum 9:30 am - Noon

Sept. 21
Harold's Plants 9 - 11:30 am
Rose Garden Center 12:30 - 3 pm

Sept. 28
Clegg's - Siegen Lane 9:30 am - Noon
Clegg's- Denham Springs 1 - 3 pm

Both Spring and Fall selections include our two easiest to grow local native milkweeds, Aquatic and Swamp (Rose) because milkweed is critical for Monarch butterfly survival.

Spring 2019 Native Plants Fall 2019 Native Plants Aquatic Milkweed Aquatic Milkweed Swamp (Rose) Milkweed Swamp (Rose) Milkweed False Foxglove Passion flower Vine (Maypop) Partridge Pea Hop Tree (Wafer Ash) Garden Phlox Buttonbush Purple Coneflower Cardinal Flower Narrowleaf Mountain Mint Ironweed

I am hoping this project will encourage gardeners to become proactive in helping the natural environment by selecting and nurturing these plants that give our butterflies and pollinators their best opportunity to thrive. Although the start date is a little ways off, please start planning now where in your garden you can add one or more of these special Geaux Grow Natives plants.

Spring Host Plants:

Aquatic milkweed: Asclepias perennis, has been native to the New Orleans area since the 1890's. It grows in sun or shade but performs better in shade. It requires moist soil and will even grow in standing water! Twelve or eighteen inches tall with a pretty white flower, it provides food for Monarch caterpillars plus attracts aphids, ladybugs, lacewings, milkweed bugs, and flower flies. Seed pods develop after the flowering stage. Zones: 6-9

Swamp Milkweed: Asclepias incarnata, likes the swamp but will also grow in sunny home gardens. Choose a sunny spot and enjoy watching insect visitation. Zones: 3-8

False Foxglove: Agalinus tenuifolia, This annual reaches three feet tall with pink flowered spikes creating a fairyland appearance. It hosts the Common Buckeye butterfly caterpillar which has electric blue barbs but does not sting. Agalinus grows best in medium moist but well-drained soils in full sun to part shade. A self-seeding annual, it is drought tolerant once established. Zones: 2-11

Partridge Pea: Chamaecrista fasciculata, hosts Cloudless Sulphur, Sleepy Orange and Little Sulphur butterflies. It is also a nectar favorite for bees and other pollinators, plus a food for birds. Grows best in full sun but will survive under shade. Zones: 3-9

Spring Nectar Plants:

Garden Phlox: Phlox paniculate, adds striking colors and months of delicious fragrance to any garden. A perennial, it prefers well drained soils and full sun but can take afternoon shade. Zones: 4-8

Purple Coneflower: Echinacea, thrives in full to partial sun, will tolerate poor rocky soil but will not grow in wet, mucky soil. Echinacea flowers provide reliable nectar for butterflies then dried seed heads for birds in winter. Zones: 3-9

Narrowleaf Mountain Mint: Pycnanthemym tenuifolium, is a member of the mint family. This stiff, erect, compact, clump forming plant grows to 30" tall. Mountain mint prefers dry to moist soil and does best in full or partial sun. Zones: 4-8

Fall Host Plants:

Aquatic Milkweed and Swamp Milkweed: -see information above.

Passion Flower Vine: Passiflora incarnata, also known as "Maypop" hosts the Gulf Fritillary, Louisiana's State butterfly, and also the Variegated Fritillary. Preferring full sun to partial sun and medium water, this vine occurs in sandy soils, low moist woods and open areas. Zone: 6

Hop Tree: (Wafer Ash) Ptelea trifoliata, is a member of the citrus family and is host for the Giant Swallowtail butterfly. The caterpillar known as the "Orange Dog" looks like bird poop as its defense against predators. Hop tree tolerates moist or dry soil and can reach up to 20 feet. Zones: 4-9

Fall Nectar Plants:

Buttonbush: Cephalanthus occidentalis, is a member of the coffee family Rubiaceae, found naturally in wetland habitats but also thrives in gardens. Its long lasting unusual globe-shaped blossoms attract pollinators and its seeds attract birds. Buttonbush is cold tolerant and can grow to 12 feet tall. Zones: 5-9

Cardinal Flower: Lobelia cardinalis, is a perennial that prefers to grow in moist, fertile soil. It likes morning sun with afternoon shade. Blooming July through September, its red flowers attract hummingbirds as well as butterflies. It's a real favorite of the Cloudless Sulphurs. The plant can reach 4 feet tall and can spread 2 feet wide. Divide in the Spring after new growth emerges. Zones: 1-10

Ironweed: Vernonia, a member of the Aster (Daisy) family, is a magnet for thirsty butterflies. Growing naturally in moist soil and tolerating brief flooding, it will reach to eight feet in fertile, damp soil. It is a sun-loving plant with loose bunches of purple flowers.Zones: 4-8

In the Kitchen with Austin

By Austin Sonnier


Smothered Artichokes

There’s nothing like fresh artichokes, and they’re in season right now! For an easy side dish or a light main course, try this recipe. I promise you won’t be disappointed.

Ingredients:

2 large artichokes

1 lemon, cut into quarters

3 cloves garlic, chopped

1 tsp. Old Bay Seasoning

3 tbs. butter

1 cup white wine or water

5 tbs. butter, melted

Your favorite hot sauce

With a serrated knife cut off the top 1/3 of each artichoke. Immediately rub the cuts with a lemon quarter, squeezing a little juice on the cuts to keep them from turning brown. Now cut each artichoke in half through the stem, from the tip to the bottom. Use a spoon to completely remove the hairy choke and all the prickly purple leaves inside the artichoke.

Melt the 3 tbs. butter in a large sauté pan. Add the garlic and sauté over medium low heat to flavor the butter. Arrange the artichoke halves cut side down in the pan. Sauté for about 5 minutes or so, until just lightly browned. Add the wine/water and the seasonings. Reduce heat to very low, cover the pan, and let cook for about 15-20 minutes. Check the pan after 10 minutes to be sure there is enough liquid in the pan to prevent burning. Add more wine/water if needed.

Test the doneness of the artichokes by piercing with a fork. It should penetrate easily. Serve the artichoke halves with the rest of the melted butter in a small dish and flavored with as many dashes of hot sauce as you like. Dip and enjoy.

Bon Manger!

Lawn Care Do’s & Don’t’s

Do's:

  • This is the prime planting season for warm season grasses such as St. Augustine, centipede, bermuda and zoysia. With the exception of common bermuda, solid sodding is the preferred method of establishing a lawn whenever possible
  • Make the first application of the recommended rate of nitrogen fertilizer for your turf variety if you have not done so. See the fertilizer recommendations on page 5 of the Louisiana Lawns Best Management Practices Guide. Do not apply phosphorous or potassium fertilizer unless recommended by a soil test.
  • Take a soil test.
  • Apply selective herbicides and sedge killers to kill off weeds growing in the lawn. You may also scout the lawn and remove weeds by hand. Make a game out of it with kids and grandkids.
  • Continue to scout for fungal damage and control with fungicides if necessary. The most prevalent is called Large Patch of Warm-Season Turfgrass. Click here to find information about large patch disease from the LSU AgCenter.
  • Apply sulfur or lime to adjust the pH if necessary according to soil lab recommendations.
  • Irrigate as necessary to moisten the soil to a depth of 4-6 inches.
  • Aerate the soil if necessary to alleviate compaction.
  • Dethatch the lawn if necessary.
  • Keep an eye open for insect pests and treat if necessary.
  • Spread fill soil and compost over the lawn to add organic material and smooth out the lawn. Do not add more than 2 inches over actively growing grass.
  • Set your mower to the correct height for your turfgrass type.

Don’t’s:

  • Do not cut more than 1/3 of the height at a single time.
  • Do not let winter weeds go to seed in the lawn.

Pruning Tomatoes-To Do or Not To Do?

By Dr. Joe Willis


When we talk about pruning tomatoes, the general understanding is the removal of suckers that form in the leaf axil on the tomato plant main stem. In addition to this, pruning tomatoes also includes the removal of tomato leaves or the thinning of fruit clusters.

First consider, why would we want to prune tomatoes? Years of field and greenhouse research have shown that, in general, pruning tomatoes increases fruit size and quality, increases earliness and decreases disease incidence. Fruit size and quality increases because the plant’s full resources are dedicated to the development and maturation of fewer fruit and less leaf and stem production. Total weight from pruned or unpruned tomatoes may not differ greatly, but the average size of each fruit and percent sugars increases, sometimes dramatically. Pruning also reduces plant vegetative density thus increasing air circulation and reducing microclimate humidity. This, in turn, reduces disease incidence because the plant canopy stays drier.

The second consideration is what type of tomato variety are you growing? There are two main types with variations along the way – determinate and indeterminate. Determinate tomatoes, or "bush" tomatoes, are varieties that grow to a compact height (generally 3 - 4'). Determinate varieties stop growing when fruit sets on the top bud. All the tomatoes from the plant ripen at approximately the same time (usually over period of 1 - 2 weeks). Determinate varieties generally produce a limited number of shoots. These varieties are usually pruned sparingly.

Indeterminate varieties will grow and produce fruit until killed by frost. They can reach heights of up to 12 feet although 6 feet is normal. Indeterminates will bloom, set new fruit and ripen fruit all at the same time throughout the season. They also continuously produce side-shoots (suckers) throughout their lifetime. These varieties are pruned heavily and continuously.

The general recommendation for pruning determinate tomatoes is to remove the suckers below the first flower cluster. Allow everything above this cluster to grow and produce.

Pruning indeterminate varieties is quite different. With indeterminate varieties, prune all suckers below the first flower cluster. Just below the first flower cluster, the plant will fork or produce a secondary main stem. It looks very different from the ordinary side-shoot (sucker). Keep this second main stem and train it just like the primary main stem. Remove suckers on each of these stems regularly as they continue to grow.

On both types, suckers should be removed when they are no more than 4 inches long. Simply grasp the sucker near the main stem and quickly snap sideways and upward. The sucker will snap right off. You can also remove suckers using snips or a sharp blade. All large suckers (over 4” long) should be removed using snips or a sharp blade to prevent tearing/stripping of the plants epidermal/cambial layer. When using a sharp blade to remove suckers, always cut away from the main stem to prevent injuring or cutting the main stem.

As tomatoes grow throughout the season, they produce new leaves as the older ones turn yellow and wither. Pruning off these old leaves as they begin to decline is a great way to keep the plant’s energy directed to the new leaves and developing fruit, it keeps the old leaves from becoming sites of infection (the plant’s resistance factors are less in the declining leaves), it increases air circulation and makes the plants look cleaner and healthier. Removing older leaves regularly is a good plant hygiene practice.

The last type of pruning for discussion is cluster pruning. Cluster pruning is the selective removal of one or more fruits from a single fruit cluster while the fruits are still very small. Cluster pruning is generally only practiced with tomato varieties that produce large, slicer type tomatoes. Cherry, grape, plum (paste), cocktail and salad tomato types do not benefit from cluster pruning. With the slicer or classic tomato varieties, to produce larger quality fruit, no more than three fruit should be allowed to mature on each flower cluster. Snip off or gently remove the terminal fruit that begin to form past number three.

Though pruning is not a necessity to have a successful tomato crop, pruning is a proven method to growing healthier plants and larger, higher quality fruit.

What’s Bugging You? – Azalea Lacebugs

Dr. Joe Willis


So your azaleas have finished flowering for now and you’re ready to starting enjoying other plants in your landscape. However, don’t neglect your azaleas or you may end up with them looking like this.

This is the result of a heavy infestation of azalea lace bug Stephanitis pyrioides not to be confused with lacewing insects. This piercing-sucking insect can be active from Spring through Fall. Infested azaleas develop stippled, bleached, silvery or chlorotic symptoms similar to those caused by mites. Even in established landscape plantings, azalea lace bugs can cause considerable damage to foliage if not controlled early in the season when populations are low.

The adult lace bug is about 1/10 inch long and cream-colored. The netted lacy wings, marked with black or brown patches, are held flat over the body with outer margins extending beyond the body outline. Under a hand lens, a characteristic hood can be seen over the head.

Females lay eggs on the underside of leaves, generally along the midrib but also on lateral veins. Eggs are covered with a dark brownish adhesive material that hardens to form a protective coating. She will lay about 300 eggs during her short lifespan. The nymphs that emerge in 2-3 weeks are colorless upon hatching but soon turn black and spiny. They will mature into adults in 2-3 weeks. There are two to four generations per year and they overwinter as eggs.

Dark spots of lace bug excrement on the leaf underside is another visible sign of infestation.

Maintaining healthy plants with proper watering and fertilization reduces plant stress as well as damage potential. Growing azaleas in shadier areas also reduces damage. Plants should be checked every one to two weeks for early signs of infestation so control measures can be employed to prevent heavy aesthetic damage.

Plants aren’t usually killed by lace bug infestations but they will be less aesthetically pleasing and will be less vigorous. Spring is the best time to control the first or second generation of lace bugs. Insecticidal soap, horticultural oil, neem oil and most synthetic contact insecticides provide good control. It is important to direct the spray to the undersides of the leaves for optimal control. Systemic insecticides such as those containing imidacloprid are also very effective but should not be used while plants are flowering.

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