It’s mid-March so the lawn care operators (LCOs) are applying their Round 1 product, consisting of fertilizer plus crabgrass preemergent herbicide. LCOs start early because it’s better to be early than late! However, any company applying a crabgrass product now MUST also apply a SECOND SHOT of crabgrass preemergent (late April to mid-May). The exception to this rule is for superb lawns, where the healthy sward is so thick and lush that crabgrass seeds have no chance to contact the soil surface. BTW, for the do-it-yourselfer it’s too early. You can wait until at least April 1st.
Nothing chaps my ass like seeing these application notifications where the company made an application over a crap ton of leaves and debris! This is usually where the damn crabgrass is going to be bad! Your lawn care company should have given you a heads up a few weeks in advance, saying something to the tune of, “Dear Customer, we’ll be applying your first round of fertilizer and crabgrass product in mid-March. Please do your best to get the leaves and organic litter cleaned up, so that our product can do its job!” This is why THE Turf Plan is so successful, because they send you timely emails–educational and informative (check out www.theturfplan.com). Your local LCOs will do a far superior job than the national chains.
If you have crabgrass in your lawn, FIRE your LCO! Right now! Crabgrass preemergent herbicides are extremely effective, so there is zero excuse for crabgrass in your lawn! This is especially true if you’ve given your LCO more than one season of business. To further reinforce this point there are new products that can be used postemergent (after the weed comes up), meaning your LCO can clean up any mistakes in mid-May.
There 3 common preemergent crabgrass herbicides that are combined with fertilizer products. The absolute best is dithiopyr (Dimension®), the second best is prodiamine (Barricade®), and the really sucky one is pendimethalin (Pendulum®, favored by that national brand!). I rank Dimension as #1 because it will actually kill small (1/2 inch or less) emerged crabgrass. If you’re a week or so late with your first shot, Dimension can kill those early emerging crabgrass plants. Look the bag over carefully and avoid pendimethalin–unless you’re sure you’ll apply that second shot. But be warned, products with pendimethalin usually have WAY TOO MUCH nitrogen (anything over 18%). You don’t want to apply a lot of nitrogen in the spring.
Crabgrass will emerge when soil surface temps reach 55F for about 3 nights in a row. If you live near agricultural areas, when the farmers start planting corn, you need to apply your first shot of crabgrass preventer. Suburbanites can use a phenological indicator, the forsythia bloom, as a guide. However, it’s not the BEGINNING of the forsythia bloom, it’s towards the END of the forsythia bloom that is more accurate (wait for that third week of yellow).
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