Herbicides – Top Ten Rules

  1. Pre-emergent herbicides block weed seeds from germinating. They will not kill weeds already up. Use the fertilizer schedule to have a healthier yard, ultimately the best defense against weeds. Period.)
  2. Once a weed is up, you need a post-emergent herbicide. For example, a broadleaf weed control for clover.
  3. There are different forms of post-emergent herbicides. Some are “selective,” and some are “non-selective.” Glyphosate herbicides (Roundup, Eraser and organic vinegar solutions) are non-selective — they kill every kind of weed or grass. Selective herbicides usually target a specific category of weeds – broadleaf, grassy or sedge.
  4. If you’re late with the application of pre-emergent herbicides, you can still do it. You just may not get total control, as some weeds may have already germinated.
  5. Observe any temperature restrictions of selective herbicides. For example, we now have cool-season herbicides for broadleaf weed control. We didn’t have that 30 years ago. And we don’t used products like Image when it’s too hot.
  6. The powdered organic Garden Weasel AG Crabgrass product from Agra Lawn was originally designed for grassy weeds, although it can control a few broadleaf weeds I have had personal success with it on Virginia buttonweed.
  7. Nutgrass and nutsedge are neither grassy nor broadleaf weeds. I recommend sedge controls for those.
  8. The granular version of Bonide Weed Beater Complete is a real one-of-a-kind product — a pre- and post-emergent herbicide in one bag. The “pre” is essentially Barricade, which blocks broadleaf and grassy weed seed germination. But the “post” only works on broadleaf weeds.
  9. Surfactants are neither applicable nor necessary for granular pre- or post-emergent herbicides.
  10. Surfactants should be added to pretty much every liquid herbicide so the treatment actually sticks to the weeds.

Wild Strawberries? It’s just a broadleaf weed!

You’re about to read everything you need to know about Broadleaf Weeds for all of Texas, but especially the Gulf Coast. But if you’ve asked about Wild Strawberries, know they are simply a broadleaf weed and everything below will work on them in your lawn, too.

I have long emphasized that my lawn care schedule is not difficult to follow and will yield results in under one year, if you just stay true to it. But through calls received on last weekend’s radio show, and at the two most recent nursery appearances (A&A Plants & Produce & RCW Nurseries) and especially via email and in Facebook posts, I’ve learned that people new to the schedule or just flat out new to the area are overwhelmed, emotionally and physically, with weeds.

It seems they’ve become frozen in that old famous phrase, “analysis paralysis”! And then they seem so overwhelmed with the weeds they have, and end up doing nothing, because they don’t know where to begin. That hesitation may be in part to the fact that my schedule is all about fertilization and pre-emergent herbicides. But c’mon … that shouldn’t stop you from killing the weeds that are up at this moment.

In early spring, there are really only two weed types we should concern ourselves with – Broadleaf Weeds and Winter Grassy Weeds. The winter grassy weed is very specific to Poa annua (wild Kentucky Bluegrass) and the broadleaf weeds are too numerous to count.

And before we dive a bit deeper on all things weed control, everyone needs to understand that once the weeds are up, we talk POST EMERGENT HERBICIDES. On “The Schedule” it’s all about PRE-EMERGENT HERBICIDE. So, let’s dive a bit deeper into early season, post-emergent weed control, so those inundated with weeds can make some headway.

We’ll start with some basics. You most likely have very unhealthy soil. The healthier the yard, the better its natural defense against weeds … with or without a pre-emergent.

Get a healthier yard by:

  1. Following the schedule
  2. Mowing at the appropriate height
  3. Keeping up good irrigation practices
  4. Aerating and compost top-dressing

As noted earlier, the vast majority of the weeds that crop up in the early part of the year can be hit with a broadleaf weed killer — a post-emergent herbicide. Cool-season herbicides, used while temperatures are still 45 -75 degrees, include Fertilome Weed-Free Zone and, the most popular and readily available, Bonide Weed Beater Ultra. I’ve always recommended liquid versions of broadleaf weed control, because granular weed-and-feeds with atrazine are so damaging to groundwater supplies and the roots of trees and shrubs. Plus, you can spot treat with liquids.

If you wait until daytime highs start creeping into the 80’s to control broadleaf weeds, then stick with the best-known broadleaf weed control, Bonide Weed Beater for Southern Lawns. Cool-season herbicides become ineffective and stressful to grass once high temperatures are consistently in the 80’s. And, as always, you should use a surfactant with any liquid weed control. Read this tip sheet to learn why – Surfactants – The Spreader Sticker.

I’ve also mentioned Bonide’s Weed Beater Complete, which works as a pre-emergent herbicide and a post emergent herbicide together. It’s sort of a 3-in-1 granular product, but the post-emergent capability is only for broadleaf weeds.

If you’ve not applied any pre-emergent herbicide, and you’re covered up with broadleaf varieties such as dollarweed, use a liquid broadleaf killer such as the Weed Beaters from Bonide to wet the leaves. Then apply the granular Weed Beater Complete. Its instructions call for wetting the area first anyway, so why not do it with the added benefit of the broadleaf weed killer. And you get the 2-in-1 pre-emergent herbicide to boot.

Most importantly, you must get only the products I name from local providers I specify. I don’t send people to big mass merchandisers because they carry other weed killers that are not formulated for southern grasses, like St. Augustine. The most obnoxious weeds that appear early in the season (dollarweed, clover, oxalis, dandelion, thistle, chickweed, henbit, wild geranium, nettle, etc.) are broadleaf weeds.

Also, as noted earlier, the only annoying grassy weed that appears early is Poa annua (wild Kentucky bluegrass), and that doesn’t usually look bad as long as you keep it mowed. Poa annua will also burn off with the heat, so I don’t pay it much attention. Prevent it altogether in November with a regular pre-emergent herbicide as called for in The Schedule. If you’re not sure exactly what weeds you’re faced with, check Texas A&M’s handy weed identification resource. https://aggieturf.tamu.edu/turfgrass-weeds/

Lastly, when it comes to broadleaf weed control in the months of March & April, the true key to success, besides getting over your own “analysis paralysis”, is to add real surfactant to the mix of the herbicide you’re spot treating with. Here’s a link to everything you’ve ever needed to know about surfactants, and actually why simply using dish soap, as we did 30 years ago, has to be swept aside, because they really aren’t just simply soap these days – Surfactants – The Spreader Sticker 

Finally, check out my Ten Rules of Herbicides and their usage. I promise that you can become your neighborhood’s weed-eradication specialist if you follow them. 

Weeds

Virginia Buttonweed
Photo Credit: Randy Lemmon
Sticky Weed/Bedstraw
Photo Credit: Randy Lemmon
Peppervine
Photo Credit: Randy Lemmon

Weeds are the bane of every homeowner’s existence!  Yes, we know that some plants that are considered “weeds” are actually wild native plants that have found their way into our urban landscapes.  But some are invasive non-natives that become garden thugs if we don’t stay on top of them.  And while we may appreciate those same wild natives in parks, meadows, and roadways, many of us live with restrictions that don’t permit cultivating them in our landscapes.  Here are our tip sheets on controlling the most common lawn & garden weeds on the Gulf Coast.  

Peppervine Control

Are you peppered with peppervine?  It truly is one of those obnoxious, invasive vines.  But it’s actually not that hard to eradicate.  In fact almost any weed and grass killer has been known to work on it.  But I’m an “old-guard” kind of peppervine killer and I do it with any of the well-known brush killer and vine killer herbicides.  

I actually get a lot of calls and emails wanting to know one of two distinct things about this vine.

  1. Is this Poison Ivy/Poison Oak?
  2. Is this like a wild grape vine?

The answer to both questions is NO!  The best way to determine poison ivy to this day is “LEAVES OF THREE, LET ‘EM BE” The leaf clusters on peppervine at the tip are usually made up of five leaves.  It can also seem sort of random and look much like Virginia Creeper does, too.

And interestingly enough, the peppervine is a close cousin of the grape, but this gives you whine and not wine!!  The whine is for real, because this is also called a Cow Itch Vine and while not as nasty as Poison Ivy’s itch, it can be really itchy for several moments, when you brush up against it. 

So, let’s talk about the rules of getting rid of peppervine:

  1. The simplest way is by pulling it out, but only if you see a sprig or two here and there. You need to get the tap root out.  This method requires persistence.
  2. Broadleaf Weed killers have been known to work on peppervines that crop up in yards, and that’s important, because everything else I’m going to recommend will kill the grass, too. Liquid Atrazine is well-known for knocking out Peppervines in lawns.
  3. Glyphosate-based herbicides, such as Eraser, Killzall, KleenUp & Roundup, can knock them out, but only where you can spray and not touch any green leaf surfaces of any plants nearby. So, my advice would be to sponge it on, rub it on, or paint it on as many leaves as possible.
  4. So, my logic then takes me to this — If you’re going to sponge, paint, or rub on a herbicide, you might as well get to the brush killer type herbicides that contain Tricolopyr or Imazapyr as their active ingredient. My advice is to always have a V-shaped piece of cardboard on the ready to protect any plants in the area you don’t want touched with a brush killer herbicide. If you see words like Brush & Stump, Stump Killer, Brush & Vine, just make sure the active ingredients are the ones listed above.
  5. There’s also the “Baggie Method” for vine control – (click here).  I have used this method for years exactly on peppervine and it works like a charm.  You simply fill the bottom 1/10th of a re-sealable plastic bag with undiluted brush killer herbicide; shove as much of the vine in the baggie as possible; seal it shut; hang it on a limb with a clothespin and voila! – in under two weeks the vine will have died, and you can clip the vine just outside of the bag and throw the whole thing away.
  6. In all cases of any liquid herbicide use, please add surfactant to the mix – (click here).

Pre-Emergent Herbicide – The Whole Story

I hear from listeners who have been disappointed with pre-emergent herbicides like Barricade and Dimension – the two most readily available on the market today. 

Some say they have more weeds than ever and are bummed because the products didn’t work as I predicted. But, as I have often noted on the air, pre-emergent herbicides are just one tool to use in keeping weeds at bay, and they are never 100% effective in blocking weed seeds from germinating.

They’re just part of the plan, along with following my lawn care schedule Randy’s Lawn Care Schedule and mowing correctly (tall for St. Augustine, reel mowers for Bermuda). Plus, Mother Nature has to cooperate – no pre-emergent herbicide will work if a recent application gets washed away with a 2-3 inch rain.

Having a thick, healthy stand of turf is a natural form of weed prevention. Weeds simply cannot germinate in a St. Augustine lawn that is mowed tall and fertilized appropriately. In my business, Randy Lemmon Consulting, I see it all the time. Lawns covered up in weeds are probably the most poorly cared for. I always see that the St. Augustine is mowed too short, and there’s no organic matter in the soil. And while some may cut their Bermuda lawns with a rotary mower, and claim they follow my schedule, I find they’ve never done a core aeration or a compost top-dressing. 

Those are all important procedures to employ if you want a good-looking lawn in the Gulf Coast region. And a single application is never going to keep a yard weed-free. Especially if it’s quickly followed by a major gully washer. Remember pre-emergent herbicides prevent weeds. Post-emergent kill weeds that are already up.  This is from one of my recent books, which we call the Top Ten Rules of Herbicides:

GARDENLINE TOP TEN RULES OF HERBICIDES:

  1. Pre-emergent herbicides block weed seeds from germinating. They will not kill weeds already up. (Use the fertilizer schedule as it will give you a healthier yard — ultimately the best defense against weeds. Period.)
  2. Once a weed is up, you need a post-emergent herbicide, such as broadleaf weed controls for clover, etc.
  3. There’s a difference in post-emergent herbicides. Some are “selective,” and some are “non-selective.” Glyphosate herbicides (Roundup, Eraser, and even organic vinegar solutions) are non-selective — they kill every kind of weed or grass. “Selective” herbicides usually target a specific category of weeds – broadleaf, grassy or sedge.
  4. If you’re late with the application of pre-emergent herbicides, you can still do it. You just may not get total control, as some weeds may have already germinated.
  5. Know the temperature restrictions on most “selective” herbicides. For example, we now have cool-season herbicides for broadleaf weed control. We didn’t have that 30 years ago. It’s also why we don’t used products like Image when it’s too hot.
  6. Although it can control a few broadleaf weeds, the powdered organic grassy-weed control known as Garden Weasel AG Crabgrass from Agra Lawn was originally designed for grassy weeds. But I have had personal success with it on Virginia Buttonweed.
  7. Nutgrass and nutsedge are neither grassy nor broadleaf weeds, which is why I recommend specific sedge controls for those annoying weeds.
  8. The granular version of Bonide Weed Beater Complete is a real one-of-a-kind product — a pre- and post-emergent herbicide in one bag. The “pre” is essentially Barricade, which blocks broadleaf and grassy weed seed germination. But the “post” only works on broadleaf weeds.
  9. Surfactants are neither applicable nor necessary for granular pre- or post-emergent herbicides.
  10. Surfactants should be added to pretty much every liquid herbicide so the treatment actually sticks to the weeds.

My fertilization schedule strongly encourages a pre-emergent herbicide in October.  The overall schedule calls for three separate applications over the year, but the October application, in my horticulturally-seasoned opinion, is probably the most important. That’s because the turf will go into dormancy once soil temperatures get below 55 degrees, and that’s when weed seeds become opportunistic. As a result, we can get overrun by clover, chickweed, poa annua and others in December and January.

If you have a thick stand of grass, and all is working well and looking good, you may be able to eliminate the pre-emergent herbicide applications on the schedule. Well cared-for turf that has a deep root system and a dense growing pattern is its own best defense against weed seed germination. But if you’re not among those folks, get as many bags as you need and get busy right now.

Spreader Settings

Photo: Getty Images

If you’ve ever consulted the spreader settings on a bag of fertilizer, you’ve no doubt discovered your spreader isn’t listed.

Heck, most of those spreaders don’t even exist anymore. The spreader manufacturers keep advancing their products every year or two, but the fertilizer manufacturers never update their information, much less do new research to verify dosage changes.

So, with help from various fertilizer experts over the years, I’ve come up with some practical spreader-setting rules that seem to work very well.

First, I don’t really have a preference on spreaders. Just be sure to use a broadcast spreader like the one pictured … not a drop spreader. Many northern transplants accustomed to growing Kentucky Bluegrass and Fescues may still own drop spreaders. If you’ve got one, you might as well get rid of it.

In Houston, you’ll need a broadcast spreader since St. Augustine is the predominant grass. Using a drop spreader on it will just “streak” it. Plus, using a broadcast spreader will save you gobs of time, cutting your passes by more than half.

So here are the general rules:

For fertilizers put the setting a notch or two above half. For example, if there are 20 notches on the spreader, 11-12 would be the setting. You don’t have to cover every square inch of turf to get good results, so if you think that’s too much, drop to a notch below half. With hand-held spreaders, if there are 5 or fewer settings open it all the way. If a hand-held spreader has 10 or more settings, put the setting a notch or two above half.

For pre-emergent herbicides, put the setting on or a notch above one quarter. (If there are 20 notches, 5-6 would be the setting.) On hand-held spreaders, if there are 5 or fewer settings lower the setting to 3, or even 2. If a hand-held spreader has 10 or more settings, put the setting on or a notch above one quarter. If your gut tells you the dosage is not enough … you don’t think it’s covering the zone that needs to be covered … then up it a notch or two.

With the advancements in spreadable composts, you can use a broadcast spreader open full.

Don’t overthink the math on this. I’ve seen spreaders with as few as 10 settings and as many as 30. You can be off by a notch or two without fear of over doing it.

Pests/Problems

Insects

Insects

Diseases

Weeds

Not really a problem once you've diagnosed it......