Monday, October 25, 2021

Yellow Leaves?


Horticulture Hotline 10/25/21

By Bill Lamson-Scribner


I’m not going to mention s$d w*bw@rm, Ar^y Wo%^s, L@$&3 P@tch or Bro%n P@tch. Here are a few things to do while enjoying the beautiful Lowcountry weather.


One thing that I’m getting asked about right now is yellow leaves or discolored leaves on gardenias, azaleas, camellias, crepe myrtles, magnolias, viburnum, … For the most part these are old leaves that are falling off and are going to make room for new leaves. With the exception of the crepe myrtle, this list is all evergreen plants and tree. Just because these plants are evergreen doesn’t mean that they never lose their leaves. Evergreens will lose many leaves between now and April, just not all at once like the crepe myrtle. I have seen many azaleas that are almost naked when the new leaves appear in late February early March (depending on the weather).


Leaves are interesting in many ways. Chlorophyl is the green in leaves that captures the sunlight and by photosynthesis (probably the longest word ever used in a Horticulture Hotline – and I spelled it right – yes!) produces carbohydrates. Chlorophyl masks the other colors of the leaf. In the fall when chlorophyl is not being produced, the other colors of a leaf are visible. That is how we get fall color - reds (maples), yellows (sweet gum).


Due to changes in available control products, mole crickets have become quite the pest again. The populations have become so high that they are doing damage in areas that they didn’t really mess with before the availability of these products went away for certain uses. Mole Crickets overwinter as adults, so they will do damage throughout the winter. Since your grass will not have chlorophyl in the leaves, it will be harder to see the damage. Your grass will already be brown. With low humidity, drying winds during the winter, if mole crickets have separated the soil from the roots, the grass plant can desiccate and die, leaving big dead areas of grass in the spring. Mole crickets fly and are very mobile so even if you kill them today they can return.    


Did you put out a preemergent product to your lawn and beds for winter annual weed control in?


I’m not going to use the words, but rainy days and warm temperatures make disease flourish in the yard, especially yards that are already under attack. T-Methyl and Strobe are two good systemic fungicides with different modes of action to avoid resistance to the disease to apply now.


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


Monday, October 18, 2021

Winterizing Turf, Trees, and shrubs


Horticulture Hotline 10/18/21

By Bill Lamson-Scribner


Yes, it is time to winterize your landscape. SeaHume should be used alone or with the 00-00-25, depending on the results from your soil test. Look for a product with a 00 for the first number (nitrogen). A 00-00-25 with sulfate of potash and minors would be great. If you do not need the potash, consider just the SeaHume, a wonderful combination of seaweed and humic acid. If you would like your yard to stay green later into the fall, try Possum Minors.


Possum Minors as its name implies is full of iron and other minor nutrients that promote ‘green ‘without top ‘growth’. By having your plants including grass plants green at this time of year the leaves can capture more sun and produce more carbohydrates to grow roots. Since the mowing has slowed down, you will be able to enjoy the ‘green’ for a longer period of time, since the ‘green’ won’t be getting mowed off. 


SeaHume will help grass, trees, shrubs, and flowers throughout the winter. SeaHume will help mitigate salt damage. The seaweed part of SeaHume has over 60 minor nutrients, carbohydrates, amino acids, gibberellins, auxins, cytokinin’s, anti-oxidants and other bio stimulants. The humic acid is also full of bio stimulants that help make nutrients that are in the soil available to the plant, help with soil structure, grow roots, and feed the microorganisms in the soil.


Trees grow most of their feeder roots over the winter. SeaHume will help grow these feeder roots over the winter preparing the tree for whatever the spring weather brings. Drought like this year?


Beware of the national ad campaigns talking about winterizing fertilizers for turf. These products are usually formulated for cool season grasses (rye, fescue). I saw one over the weekend that was a 32-00-10. Not exactly what we want to put on our yard in mid-October in the Lowcountry. Just ask Clemson University.


Have you ever had winter kill? Now is the time to prepare your grass for the wide variations in temperatures we have. If you had winter kill in the past, you need to be sure to correct low and poorly drained areas, reduce thatch in the yard, increase air movement in low areas, keep your lawn hydrated and feed (with the right food for the winter).


Mow your grass lower than normal (centipede 1.0 to 1.5 inches, St. Augustine 2.5 to 3.0 inches). By mowing your grass lower, you will increase the air movement around the crown of the plant, so cold air will not settle at the crown of the plant and damage the grass. In Florida helicopters fly low over citrus groves that are in valleys to get the cold air out. Tall grass or thatch will insulate the crown of the plant like a goose down jacket, keeping the cold air near the crown where it can cause winter kill. Centipede lawns usually get winter kill the worst if temperatures plummet quickly.


Fine blade Zoysia grass can grow very dense and get thatch. De-thatching, verticutting, using Bio Grounds Keeper, and regular topdressing should be part of your maintenance schedule.  




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


Monday, October 11, 2021

Fall In The Lowcountry


Horticulture Hotline 10/11/21

By Bill Lamson-Scribner


While walking and driving around, it seems that brown patch/ large patch/ Zoysia patch (I will use these names interchangeable) has invaded the Lowcountry in a big way. As the cooler weather comes and the grass growth rate slows down, large patch / brown patch / zoysia patch fungus began to show up in our lawns. Does it seem to you that right when we got the army worms and sod web worms under control, here comes the large patch? Proving once again, the Lowcountry is the hardest place in the world to grow grass and why it is so important to have a program for your lawn. Do you see areas of your grass that are brown when other parts are green?


Large patch disease is always present in the lawn, it just manifests itself when the environmental conditions are right and your grass cannot outgrow the damage. Without any sustained cold temperatures, this disease is slowly spreading across lawns as the temperatures that favor its growth keep coming into play. This prolonged fall is great for outdoor activities like visiting local plantations, fishing, boating, golfing, shopping and working in the yard; however, the temperatures are also perfect for these diseases to develop. The grass is not fully actively growing (not mowing as much) and it is not fully dormant (brown), so these are perfect conditions for the disease to attack.


Since this disease is a big problem in the Lowcountry, knowing that it is a soil borne disease can help you with control strategies.  Being a soil borne disease, you know that it will reoccur in the same areas year after year.  There are not any spores flying through the air like many of your leaf spot fungi, so the disease is easier to control.


As a soil borne fungus, if you map the areas that you have the disease, you can concentrate your control efforts (dollars) into a smaller area, putting less control products into the environment.  If your yard is 5,000 sq ft usually you might have a few infected areas which might total approx. 500 ft.  Instead of using control products to treat 5,000 sq ft, you can concentrate your efforts into the 500 ft (i.e. 10% of your total yard).  If Large Patch was an air borne fungus with spores, you would have to treat the entire yard because air borne fungi spreads a lot quicker than soil borne fungi.


As your grass is going into dormancy and the temperatures begin to cool at night, large patch is ready to attack your grass. Large patch will go inactive when the temperatures get very cold; however, it will become active again when the temperatures favor the disease. If you have discolored areas in your yard that appear to be a disease, check with someone that knows. Even if it is during a cold phase and the disease does not appear to be active, you can still put out a systemic fungicide for protection. Our soils do not get so cold that the plant will not absorb the fungicide with its roots. Remember treating a fungus with a systemic fungicide is like getting a flu shot – you do it preventatively before you have the disease. If it is too late to use it preventively, when you want the disease to stop spreading, you can use the fungicide curatively.



A good granular one-two punch control strategy is T-Methyl and Strobe Pro G (all systemic fungicides that get into the plant).  Use these products in areas where you have had Large Patch previously at the preventive rates and intervals recommended on the labels. Be sure to use T-Methyl with Strobe Pro G, so you are switching chemistry classes and modes of action. Good control early on can help avoid flare ups in the spring also.


Large patch usually likes wet, heavy thatch, improper nutrition, and/or compacted soils.  Culturally you need to manage your irrigation system, raise any low areas, and correct drainage problems.  Reducing thatch (at Possum’s we have a great organic granular product for controlling thatch), maintaining proper fertility levels, and aerating to alleviate compaction, will also help control large patch. A healthy turf (following soil test derived feeding schedule) with a soil with a lot of bio-diversity (use of cotton burr compost, SeaHume and other organics) has shown to help manage this disease.


It is a great time to apply Wet & Forget for a little fall cleaning. Great product unless you are in the dog house for something or need immediate results. You spray the product then it slowly starts cleaning. In two weeks, you usually can see a big difference, and it continues to clean for a while afterwards.


Time to take soil test. Every soil test is unique to your yard. Time to get ready for 2022.


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