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Dan West Garden Center February 2008 Newsletter© Dealing with Weeds, and a few February chores Greetings class and welcome to Weeds 101: A pre-emerge herbicide is the most important part of a weed-free lawn or garden and the most misunderstood. You don’t “see” them kill anything. The chemical forms a barrier at the soil surface that kills seed as it germinates. Any weeds you can see (well most of them anyway) will not be killed by a pre-emerge. You need a post-emerge for that. So let’s talk a little bit about both. First, the pre-emerges… Timing is critical when applying pre-emerges. You want to apply the product approximately 30-45 days before your target weeds will germinate. Most spring germinating weeds come up as the ground warms up and the danger of frost has past. Here, that’s usually late March to early April, so you want to apply your pre-emerge in mid to late February. That way, you have 30-45 days for rain to “spread out” the chemical to form the protective barrier on the soil surface. Any digging or cultivation in a bed after you’ve applied a pre-emerge will destroy the barrier, so in most cases you should plant, then apply. Fall germinating weeds usually start coming up in late October as the ground begins to cool and rains become more frequent, so mid September is our target time in the fall. If we get mid summer rains from hurricane remnants, or if you are watering a lot, then mid August may give you better results. Some products are limited to twice a year applications, but many are not, so often I apply another round of pre-emerge in late May, especially if we’ve had an exceptionally wet spring. Remember these products kill germinating seeds so you DO NOT want to apply them in areas that you may need to reseed. There is at least an 8 week, and as long as 7 month, waiting period to reseed depending on which product you use. Here are some of your options: Hi-Yield Crabgrass Control - This granular product contains a blend of Balan (benefin) and Treflan (trifluralin). It’s labeled for use on Bermuda, Perennial Bluegrass, Centipede, Fescue, Perennial Ryegrass, St. Augustine and Zoysia. A 9 lb. bag covers about 4000 sq. ft. for spring crabgrass control but should be applied to 2500 sq. ft. for fall control of annual bluegrass (Poa annua). If you’ve had heavy infestations of annual bluegrass, I’d put down a second fall application about 10 weeks after your first. It also controls foxtail, goosegrass, barnyardgrass and gives moderate control of woodsorrels and spurges. Ferti-lome Lawn Food plus Crabgrass and Weed Preventer - This granular product contains Barricade (prodiamine) in combination with a 16-0-8 fertilizer. It’s labeled for use on the same turf grass varieties as above, but you’ll only apply this product twice a year. It lasts longer and controls a wider variety of weeds and grasses including knotweed. A 20 lb. bag covers about 5000 sq. ft. Hi-Yield Turf & Ornamental Weed & Grass Stopper - This is my personal favorite and it contains Dimension (dithiopyr). It can be applied at rates from 2.4 to 9.2 lbs per 1000 sq. ft., depending on the type of grass you have, and the length of control you want. This product is unique, because unlike the previous two we’ve talked about, it’s not just for turf. It can be used in and around ornamental flower beds. At the higher rates it also kills crabgrass up to 4 weeks after it has germinated. Dimension is available, in granular form, in a 12 lb. and 35 lb. bag and we also have it in a liquid concentrate (pint) that’s applied at 1.5 oz. per 1000 sq ft. Weed Impede - This is a liquid, hose end applicator pre-emerge for flower beds, groundcovers, walkways and around trees and shrubs. This product contains Surflan (oryzalin). This is easy to use and a 30 oz. bottle covers about 1,250 sq. feet and an application lasts about 4 months. I know all of you have more, but the typical home only has about 250 sq. ft. of flower beds, so one bottle will last a couple of years. All of the above products have one thing in common…They should not be used around fruit trees or in and around vegetable gardens. We do have a couple of products for use on your fruit and vegetable gardens: American Herbicide Granules – This product contains Treflan (trifluralin) which is approved for use in your vegetable and flower garden. Read the label carefully to determine if you should use it before or after seeding or transplanting. In our heavy clay soil, the rate is 1 lb. per 640 sq. ft. It’s available in a 4 lb. jug, a 15 lb. bag and we have in a liquid (pint) also that is applied at 3 oz. per 1000 sq. ft. Strawberry and Fruit Tree Weeder - This granular product contains Devrinol (napropamide) and is the only product now labeled for use by homeowners in strawberries. It can be used around fruit trees and many groundcovers, flowers, shrubs and trees. It comes in a 7 lb. jug that covers 3,000 sq. ft. Corn Gluten – This is an organic pre-emerge. It works the same way as other pre-emerges and is labeled for vegetables, herbs and all ornamentals but it should only be used around established plants. We have it alone or in combination with an organic lawn fertilizer by Espoma. IMPORTANT: Read and follow all label instructions. Some of the above products have plants or cultivars listed that have been shown to be sensitive to some pre-emerge. Once you‘re on a pre-emerge program for a year, you’ll stop most weeds from coming up, but you’ll still have to deal with the weeds that you already have. Many weeds are perennial. When you see dandelions in bloom, they’ve already been there a year. That’s where the post-emerge products come in… Image – is a selective herbicide that stops cell growth. It controls a wide variety of broadleaf weeds (including wild onions), nutsedge and annual bluegrass. It can be used on bermudagrass and Zoysia when they are dormant or when they are actively growing. It should not be applied when the grasses are going into, or coming out of, dormancy. This year we have Image in a “ready to spray” hose end sprayer, so there is no mixing. It should not be used on Fescue. Image should be “watered in” within a few days of application. Ferti-lome Weed Free Zone – This is a selective broadleaf weed killer. It contains Trimec, (a blend of three herbicides we’ve had for years, 2,4-D, MCPP and dicamba), and adds a fourth, Carfentrazone which works well in very cool weather (40’s) and is one of the few products that will control Virginia buttonweed. It’s approved for use on any Mid-South turf grass, though some slight yellowing may be noticed on hybrid bermudagrass and St. Augustine. This product should be used when the temperature is below 90° and should be applied as a “spot spray” only under and near trees. Best results are achieved when no rain occurs within 48 hours of application. Hi-Yield Turflon - This is a specialty herbicide for those of you with fescue lawns. It contains triclopyr and is an excellent broadleaf weed killer with the added benefit of killing bermudagrass too. Once the spring germinating grasses have matured, and the temperature has risen above 85°, we move to another product… MSMA– This product kills “grassy” weeds in the lawn such as crabgrass, goosegrass, foxtail, wild barley and nutsedge (with repeated applications) and we have it in several formulations. For best results, you should mow and then spray immediately afterwards. The hotter it is the faster and better it works. SedgeHammer – (formally Manage) is a selective herbicide to kill yellow and purple nutsedge (nutgrass) in turf and landscaped areas. It can be tank mixed with glyphosate (Killzall) and used around ornamentals, or for lawn renovation. Hi Yield Weed and Feed – This is a granular form of Trimec in combination with a 15-5-10 fertilizer. Most fertilizers should be watered in, but not weed and feed products. YOU MUST WATER FIRST AND APPLY THE PRODUCT TO WET GRASS! The herbicide must stick to the foliage to work properly and best results are achieved if there is no rain for 48 hours. Do not apply weed and feed products under or near the drip line of desirable trees. IMPORTANT: Read and follow all label instructions. Many herbicides have temperature restrictions and most need to be used sparingly around trees. “Are there other options, if I don’t want to use weed killers?” Yes. Herbicides are just a part of a weed control program. Properly mulched beds will have few weeds coming up from seed. Landscape fabric may be an option in some areas and proper maintenance (correct mowing and fertilization) of lawns to form a dense mat of turf will stop most weeds, so ultimately you’ll only need occasional herbicide applications. Another option is “pull them”. Its good exercise and excellent therapy, but herbicides are a better option for me, because in the last few years my legs have been getting longer and the ground is not reachable unless I’m sitting on it! And then there’s the “just mow them and they all look green” method which works for a number of people. February is a good month to lime your lawn if you need to. Proper pH is critical to develop a thick, matted turf, a good flower garden or healthy boxwoods, so check your pH. We’ll be happy to check it for you for free, just bring us about a coffee can full. February is also a good time to prune and spray roses. Prune first, there’s no point in spraying what you are about to cut off and throw away. Then spray with a mixture of lime sulfur and dormant oil. Remember to spray the ground around the plant also. February is a good month to do the January chores you didn’t do, so read the January newsletter if you didn’t do that either. Beginning February 10th, Dan West will be open on Sundays again from 11 AM until 5 PM. Don’t forget to check out our current specials on our homepage at Our next class will be on new items for this spring. Class dismissed.
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