Weeds, Weeds, and More Weeds

Horticulture Hotline 1/30/17

  Bill Lamson-Scribner

Winter weeds seem to be in rare form this year. Chickweed is what I’m seeing most as a broadleaf weed and that annoying annual bluegrass is maintaining its place at the top of the grassy weeds division. Right now is the time to kill these weeds before they produce seed for next year’s crop.

With the warm winter, we have had, you will probably get your best results if you mow your lawn (and weeds), wait 2 or 3 days, apply a weed killer, then wait a week or two before you mow again. You want the weeds to be actively growing, so they absorb the control product. Then you want to give the weed time to translocate the active ingredient before you mow it again.

Henbit, clover, Florida Betony, lawn burweed (definitely want to kill before the burr is sticking your feet – Gamecocks call it Spurweed)), hairy bittercress, Carolina geranium, thistles, dandelion, and the list goes on… are some of the weeds being a pain in the grass.

Weeds are much easier to kill now while they are actively growing in the vegetative part of their life cycle then when they are in the reproductive part of their life cycle (usually March  / April here depending on the weather – this year seems a little early). Kill the weeds now! The PHD doctors have figure that one annual bluegrass plant produces 2500 viable seeds. Think about what happens if your weeds are not maintained for a year or two. In one year that is 6,250,000 weed seeds, after that my calculator errors out!

Your grass doesn’t usually like to be treated with herbicides while coming out of dormancy (in transition) either, so it is much better to control the weeds now while the grass is dormant.

With preemergent time for summer annuals coming up so quickly, I plan to treat for the winter weeds that are growing now and put out a preemerge at the same time. By putting out the pre and post emerge, I will prevent any sneaky late germinating winter weeds that will try to pop up and re-seed themselves this spring.

At Possum’s (and many other local stores) we have many different herbicides to meet your needs to kill your weeds!

There is a Fungus Among Us

Horticulture Hotline 01/23/2017

By Bill Lamson-Scribner

The basically warm, high humidity winter has finally made fungus explode throughout the Lowcountry. I don’t like to cause panic. We have only sent out one email alert in 14 years from our stores. (If you would like to get on our email list, stop by any of our 3 Possum Landscape and Pest Control Supply stores to sign up.) The rains of 2015 and 2016 (Matthew) really spread the fungus to new levels. These new areas of infection are showing up now with the perfect environmental conditions and are likely to show up again this spring. Be ready. Fungicides work like the flu shot – they are best to be used preventatively before you have the disease. Unlike the flu shot, if you don’t get it out in time, there are curative rates you can use.

Large Patch or Brown Patch fungus loves these weather conditions. Temperatures at night in the high 50’s to low 60’s and moisture make conditions real favorable for Large Patch or Brown Patch fungus. We have had plenty of these conditions making the fungus environment perfect for the spread of this disease. Fog, rain, no sun (Saturday I heard someone blame the weather on Trump) and the perfect temperatures has caused disease on areas I have never seen disease before. With these weather conditions, you see those round, yellow areas of disease. Or sometimes the whole yard is covered in disease. Walk through your neighborhood, you will see what I mean.

Since it is very difficult to control night time temperatures and humidity, you can put your efforts into doing other cultural things to help minimize the disease. Large Patch or Brown Patch fungus 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 (now or when the grass is growing - BGK 7500, when grass is growing - aeration or dethatching), maintaining proper fertility levels via soil testing, and aerating to alleviate compaction, will also help control Large Patch or Brown Patch fungus.

Certain organic products have shown to increase microorganisms in the soil that compete with plant pathogenic fungus in the soil. At Possum’s we get good feedback from Nature’s Blend, SeaHume, Crab Shell, Corn Gluten, Cotton Burr Compost, and some of the Roots products. These products are not fungicides; however, people that use them report back to us that they notice less fungus in the yards that they apply these products. Coincidence or real science? I’m thinking real science because I have noticed it in my yard too. Try some of these products in areas that you know you get the disease, and see how it works for you.

Since the grass is semi-dormant, a systemic control product like T-Methyl or Fame might be a good idea to get you through the next month or so as long as conditions are favorable for the disease. Be careful because some of the fungicides in the SI or DMI class (Bayleton) of chemistry slow down the growth of the grass making the grass more susceptible to fungus. Actively growing grass will recover faster from disease.

Being a soil borne disease, you know that it will reoccur in the same areas year after year.  If the base of a leaf blade with Large Patch is moved from one part of the yard to another (lawn mower – not real likely if you have sharp blades), this can begin a new infection area; however, these are not spores flying through the air.  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 buying 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 had to treat the entire yard because air borne fungus spreads a lot quicker than soil borne fungus.

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

Crepe Murder, Its Just A Shout Away

Horticulture Hotline 01/16/17

By Bill Lamson-Scribner

The question about pruning Crepe Myrtles and other plants seem to top the list of questions for this week. The butchers are out there! The time is now for getting in your soil test, so you can amend the soil by spring time. Do you have any disease prone plants (roses, etc.) that could benefit from a little sanitation? What is the population of moles in the Lowcountry? What is the population of moles in your yard? Have you applied Neem Oil for overwintering insects and disease?

Crepe Myrtles are the most abused tree in the landscape. Since they bloom on new growth, someone “topped” them a while back and notice the flush of new growth and the prolific blooms. These heavy blooms are supported by wimpy 18 – 24 sprouts that just developed that growing season. When it rains, the bloom catches water and becomes even heavier. The bloom will hang down and eventually the wimpy new growth supporting the bloom will split off tree leaving an open wound for insects and disease.

Instead of “topping” the tree to increase blooms, a good fertility program will accomplish the same thing without ruining the beautiful natural branch structure of the tree. A soil test and program can guide you to the right fertilizer for your tree. Have you ever seen a Crepe Myrtle in the winter when the leaves are gone, and sense the tree’s embarrassment, like a dog with the cone on its head? A tree that has been “topped” is standing there naked of any foliage with these big nasty swollen knobs at the end of the branch, like huge warts. The tree that is pruned correctly is standing there naked and proud, like a nude Greek Statue.

The correct pruning for a Crepe Myrtle involves removing dead limbs and crossing limbs. Any limbs growing toward the middle of the tree are good candidates for removal. If a limb is growing to the outside of the tree let it be. Opening up the center some for sunlight penetration and air movement is always a good idea to help prevent disease. Sometimes Crepe Myrtles, being a multi-trunk tree, can have too many canes growing from the ground, and one of these needs to be removed. Removing these canes is best done while the tree is very young; however, you can prune these canes out once the tree is older.

There is a very rare occasion that a landscape designer orders that a tree should be topped. Under certain circumstances usually involving safety concerns or visibility concerns a designer will recommend keeping the tree at a certain height. When I worked on Hilton Head, we had a safety situation by a guard gate that required us to “top” the Crepe Myrtles; however, we did not “top” the other Crepe Myrtles in the project. Some businesses want their sign to be seen, and Citadel Mall is practicing pollarding, a type of severe pruning that the Crepe Myrtle can tolerate.

Now days, Crepe Myrtles are available in all different sizes from 3 feet to 30 feet, so planting the right one to fit the scale of your landscape is crucial. Much of this “topping” can be avoided with the proper plant selection and proper fertility. Whoever is planting the tree (or any plant) should look at its mature height and spread. Then plant the right plant for the space.

If you live in Mt. Pleasant, learn the local ordinances because they have laws about the proper pruning of Crepe Myrtles.

After you prune your Crepe Myrtle properly, now is the perfect time to add Cotton Burr Compost as a mulch, SeaHume as a biostimulant and minor nutrient treasure chest, and a tree and shrub drench for insect protection.

Spring is coming. Preemerge?