Monday, May 17, 2021

Citrus Leafminers and So Much More!


Horticulture Hotline 05/17/21

By Bill Lamson-Scribner


If you like the fragrance of magnolias and gardenias, what a great time of year to work in the yard or take a walk. Two weeks ago, I was smelling the thick intoxicating smell of banana shrubs, and now, the clean smell of the gardenias and magnolias. The weather has been cool, making those outside jobs enjoyable. The cool nights also have slowed the grass where it is not actively growing in some areas (zoysia is extra slow waking up). In some areas it seems like the grass is a month behind.  


1.      The Citrus Leafminer Pheromone Traps have been doing a great job! If you put them out in February, it is time to put out new ones. They “last up to 15 weeks”. As good as my foliage looks, I’m not going to risk expecting them to last 15 weeks! I have already seen the nasty rascal chinch bug in St. Augustine grass, grass feeding worms, and at Possum’s, we are already selling a lot of flea killing products (fleas loved the moist fall).  If you have St. Augustine grass, be sure to put out a product labeled for chinch bugs such as Allectus, Bug Blaster, Bifen or Lebanon Insect Control.  Pulling into your driveway to a dead lawn after a family vacation is not the “welcome home” you want.

2.      The cool, dry nights make powdery mildew on plants and large patch on lawns a problem.  Roses, Crepe Myrtles, Dogwoods, Verbena and Gerber Daisies are a few plants that I would check for powdery mildew.  Powdery mildew is a white substance that grows on the tops of the leaves.  As the lawn tries to figure out whether it is still winter (nighttime temperature still in the 60’s), or summer (daytime temperature in the high 80’s), Large Patch (Brown Patch) is prevalent.  For powdery mildew, Honor Guard, Fertilome Systemic Fungicide, or Neem PY (organic) will do a good job.  For Large Patch consider T-Methyl, Strobe or Serenade (organic) in active areas. 

3.      While driving through neighborhoods localized dry spots were very evident when we had that dry spell.  These are areas in the yard that turn that bluish gray color from lack of water.  New neighborhoods with young grass and poor soils seem to be most susceptible to these dry areas.  Exposed areas with lots of wind and areas at the beaches also are good candidates for these localized dry spots.  Adding organic matter to the soil (Cotton Burr Composts or SeaHume), wetting agents, or adjusting sprinkler heads will help with these dry areas.  Remember to water in the early a.m. before the wind picks up, so the grass will dry by nightfall.

4.      Moles seem to be particularly active this spring.  They just had their young in April and now they are tunneling up a storm.  The young moles are hungry!  Manage the food source in your yard (grubs, mole crickets) with Lebanon Insect Control and go after the mole with Mole Patrol. Repellex will do a good job of repelling them, if you would rather go that route.

5.      As with all products, you should read and follow product labels.  More is not better when dealing with control products.  Know your square footage and watch overlapping when applying your products.  You also need to watch the weather forecast to ensure the products have a proper amount of time on your target pest prior to any rain.  If the product needs to be watered into the ground, a slow watering by a sprinkler is better than a gully washer from the sky.  A very hard rain can wash products into the storm water drains which are bad for the environment and you have wasted a lot of money.

6.      Also sweep or blow fertilizers or control products off of hard surfaces when you

      finish applying them. In the case of fertilizer this may prevent staining, and            most importantly it will keep products from washing through storm drains to the     marshes.


Always read, understand and follow product label. The product label is a Federal Law.


Monday, May 10, 2021

Wasps, Flies, Fire Ants, Mosquitoes


Horticulture Hotline 05/10/21

By Bill Lamson-Scribner


Wasps, flies, fire ants, mosquitoes – oh my!


Digger wasps are continuing to multiply in numbers in the Lowcountry. At Possum’s we use to get a few complaints in localized areas, now the numbers seem to be on the rise. One faithful reader of the ‘Horticulture Hotline’ sent me a 14-page letter describing the progression of damage to her yard. I saw an old friend in the grocery store and a conversation that would have dominated by fishing stories or stories about old times was dominated by ground bees. The presence of wasps is intimidating and unsafe.


Digger wasps start out as just a few holes in the yard. The holes are where the adults lay their eggs. In the spring, the young emerge. In the fall these wasps are now adults and they dig new holes and lay eggs for the following spring. In a very short time period, you can go from having a few digger wasps to thousands. All these holes can ruin your turf areas and the wasps make it less enjoyable to be in the yard.


Most of these wasps are predatory feeders. They eat grubs (should manage for moles and potential turf damage), small flying insects and ground dwelling insects (mole crickets, grubs). The wasps sting the prey to death, then bring the dead prey back to the wasp’s hole (nest), then lay an egg on it so the young have an instant food supply when it hatches.


All control should be done at dust or at night when the wasps are in their hole. You need to plan on several applications of products to manage this pest. Since the wasps eat insects in your yard that you should be managing to certain thresholds, going after the wasp as well as their food source should benefit you greatly (like the mole). Since the wasps like subsurface insects, Sevin would be a good product to start your management program. Who knows you might kill a fire ant or the nasty rascal the chinch bug as a bonus?


If you just have a few holes, D-Fence Dust is a great product. At night treat in and around the hole. When the wasp land near the hole and go into the hole, the dust gets on them and kills them. The wasps also transfer the dust between themselves. Some people will also “plug” the hole. At Possum’s we sell the plugs, but you could possibly use something from around the house. Be sure to turn off the irrigation and check for rain. After you use the dust, it would be best for the area to stay dry for the night.


If you have many of these uninvited guests, DeltaGard G or Turf Ranger could be used across the whole area. Remember they fly, so getting your neighbors involved is crucial. These products need to be watered in to get to the target. Turf Ranger recommends ½ inch of water. Water the product in slowly so the product soaks into the ground, and does not run off into a non-target area. Apply these products when you first see the wasps and until they are gone, waiting at least one week between applications.


EcoVia is a National Organics Program compliant product that is labeled for wasps and other small flying insects (mosquitoes – yeah). EcoVia is safe to use around water, kids, and pets. Consider using EcoVia in your product rotation.


When treating always wear dark clothes and have a can of wasp freeze on your person. Digger wasps did not get there overnight, and they are not going to go away overnight.


Ants seem to be coming to the surface despite the dry weather, and I’m seeing mounds everywhere. Grilling, here come the nasty flies. No telling what they landed on before they landed on your dinner, especially if you have a dog. Wasps in bushes, in the corners of your doors, in your grill, on your gutters, on your outdoor furniture, everywhere! Have you heard that familiar sound by your ear that a mosquito makes recently?


Always read, understand and follow product label. The product label is a Federal Law.


Thursday, May 6, 2021

Mulch Happens

Horticulture Hotline 05/06/21

By Bill Lamson-Scribner


Pine straw is in short supply. Oak tree worms won’t stop coming down. Should I color my mulch with a spray dye to give it that new look?


Here are a few general facts about mulch. 


·         In the old days, the recommendations were the more mulch the better up to 6-8 inches. The latest research only recommends 2-3 inches. 

·         Always wait to apply mulch in the fall until after the leaves have dropped from your deciduous trees. In the spring wait for the late leaf droppers like Live Oaks and Water Oaks to drop their leaves and ‘worms’. 

·         Be careful not to apply mulch right up to the trunks of plants, shrubs or trees.  The trunk has a different cell structure than the roots and cannot handle prolonged periods of moisture.  The moisture will soften the tissue and allow disease and insects to attack the trunk, or the trunk will send out adventitious roots. 

·         The main purpose of mulch is to buffer the temperature extremes and suppress weeds.  If your soil is naturally wet, it is better to have a very thin layer of mulch so that the ground dries out quicker. If your soil is dry, a thicker layer of mulch will help hold the water in the soil longer. 

·         When applying mulch around your house, try to keep an 18-24 inch mulch-free zone from the base of your home. You don’t want to give termites a way to breach the protective barrier around your house.  You might even contact your professional pest manager to inform him that you have added mulch to your beds. 


Now days there are many synthetic mulches (synthetic pine straw, mulch made out of ground tennis shoes, mulch made from ground tires), also rocks, and dyed wood mulch that will keep their color longer.  These mulches look good but will not add organic matter to your soil (except the dyed wood mulch). 


When your pine straw has turned a little white but still looks clean, you can spray on some Brown Mulch Reviver (Possum’s Brand). Just fluff up the straw with a rake and spray it and you have “new” mulch. You can even add weed killer or preemergent products and kill/prevent weeds at the same time. Since you don’t want to pile on mulch year after year this could save a lot of time and money. When I was working on Hilton Head Island, we did this with great results. I know some landscapers here that use this product as well and like it!


There are many types of wood mulch (hardwood, double shredded hardwood, pine nuggets, mini nuggets) that over a period of time will break down and help the organic content of your soil.  Wood mulch will add more organic matter over a period of time, than the pine straw.


If you like to have your cake and eat it too, you can apply Cotton Burr Compost at a depth of 2 inches and cover it with pine straw or wood mulch and this would immediately benefit your soil.  Every time it rains or your irrigation runs, your plants would be receiving a tall drink of compost tea chocked full of nutrients.  This combination would also feed the beneficial micro-organisms in the soil and not tie up any nitrogen.   You can have the neat tucked appearance of pine straw or wood mulch and get the nutrients from the Cotton Burr Compost that will immensely improve your soil. The people (and their plants) that have tried this method have been extremely happy!


Get out your preemergent product of choice, SeaHume, insecticide for fire ants and mole crickets, mole killer or repellent, and preventive fungicide. Rats, roaches, fleas?


Always read, understand and follow product label. The product label is a Federal Law.