Monday, February 6, 2012

Preemergent Products

Wow, the weather is crazy. Daffodils showing color, Prunus trees blooming (Cherry, Peach, Crabapple) and the soil temperature indicates that it is time to apply preemergent products to your beds and turf right now. I know many of you are used to waiting for Valentine’s day (a great present by the way) or the running of the Daytona 500 to apply the magical weed preventer; however, this year is shaping up to be a little different.

Depending on which PHD doctor you believe, crabgrass germinates when the soil temperature (3 inches deep) stays above 55 degrees (some people say 57 degrees), for 3 straight days provided adequate moisture in the soil. Now some doctors say remains 57 degrees or above for 24 hours at a depth of 3 inches with adequate moisture. The soil temperature is above this range now. Do not delay, get your preemerge out now.

For those new readers of the Horticulture Hotline, preemergents kill weeds as they germinate. The weeds never come up and you never have to worry about them. Crabgrass, goosegrass, barnyardgrass, crowfootgrass, dallisgrass (seedling), foxtail, annual bluegrass, smutgrass, barley, kikuyugrass, wild oats, bittercress, carpetweed, chickweed, Carolina geranium, henbit, knotweed, lespedeza, marestail, black medic, mustard, oxalis, pineappleweed, pigweed, redroot, parsley-piert, purslane, rocket, shephardspurse, speedwell, spurge, and woodsorrel are examples of weeds controlled by preemergent products. Small seeded annual weeds are controlled by preemergent products.

Clover, Florida Betony, Nutsedge and Dollarweed are not controlled by preemergents. These are perennial weeds. Weed Free Zone is a liquid that will do a good job on controlling many of your broadleaf weeds. The nutsedge will require a different product and is most likely not visible right now. It is important to control these weeds now before they go into their reproductive stage. A weed in its reproductive stage is harder to control than a weed in its vegetative stage. By killing the weed now you avoid having to deal with more weed seeds next year.

With the warm weather we have had, it is very noticeable when you ride through the Lowcountry which homeowners and which businesses use preemergent products last fall at the correct time. One business or home lawn will be nice and brown and dormant with-out a spec of green in sight. Right next to it will be brown turf mixed with green weeds. Again, it is very important to control those weeds now before they begin to flower.

If you want to control the Sweetgum balls, now is the time to arrange that treatment. An arborist can inject Snipper now and the balls will not develop into the nuisance in the landscape that they would otherwise. Call right away as this is a timing issue as well.

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