It's that time of year when we start thinking about spring green-up and which pre-emergents we're considering. Hopefully everyone has gotten their lime out from my last newsletter. If not, it's not too late to lime and get that Ca and Mg out and incorporated into the soil with a good aerification.
If you got your potash out in the fall, this will certainly help with spring dead spot. Adequate P and K have been shown to help suppress spring dead spot. If you are battling spring dead spot, then you know the time to treat it is in the fall with two applications of fungicides (Headway, Eagle), and one spring fungicide application (Velista) will certainly help in severe cases.
In extreme cases, using a turf stripper in early summer gives the best results. This removes everything from the shoots to the layer of thatch above the soil and roots, where this fungus lives. If you have established turf, choose a pre-emergent that better fits your needs, your soil and any weed infestation you're battling. Dimension or Prodiamine will help with some grassy weeds and broadleaf weeds. Some people use Specticle, which is really good and really expensive. I prefer to use that pre-emergent in the fall.
If you have new sod, sometimes you are better off allowing the turf to get established and just treating the weeds that have emerged with a post-emergent. Most pre-emergents are root inhibitors, and this will affect the roots on new sod. If you have the budget, you can use Ronstar on new sod without affecting root elongation. If you can do split applications of your pre-emergents, this allows a longer window of residual — essentially making it last longer with better control.
Lastly, the question is always: "Do I scalp, or do I not scalp, for an early spring green-up?" I have seen many times that when you scalp, it is actually slower to green up. If you scalp too low, you remove the crown where the shoots elongate from, essentially killing it. If we get a cold snap, the grass is more susceptible to those winter temperatures, and it's so stunted that it doesn't green up until mid to late summer. Sometimes you are better off doing a good aerification, which allows for good gas exchange. When that hard, compacted soil is broken up after a cold winter, water can move freely to the roots, creating longer, stronger roots and a greener, healthier plant.
If you have any questions about pre-emergents, post-emergents or cultural practices, please feel free to call me, because here at Sodmasters we want you to enjoy that grass outside with family and friends, creating memories — barefoot, feeling that cool grass under your feet, taking in that free vitamin D.
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