By Jack Fry
Looks like we’ve got a short-term period of cooler temperatures over the next several days. Midsummer heat relief is good for us, and it’s also a great time to do some of the cultural practices we often avoid during midsummer heat.
Creeping bentgrass and annual bluegrass don’t like the heat, and really don’t appreciate it when we implement certain cultural practices during hot weather. On greens that have shallow roots and experience indirect heat stress, any kind of stress brought about with cultural practices can sometimes be the “straw that breaks the camel’s back.” Consider implementing some of the following during short stretches of cool weather:
1) Solid tine aerification. Opening up the surface of the green can help get oxygen to roots and prevent a “sealing off” of the surface that can arise when organic matter accumulates.
2) Verticutting. Using vertical knives to cut leaves and stolons is certainly a stress to the plant, and now is a good time to do it if your greens are grainy (a la Johnny Miller!), or are accumulating more organic matter at the surface than desired.
3) Sand topdressing. Topdressing during midsummer can be stressful to the plant especially if it the sand is dragged into the surface.
4) Product applications. Some products can potentially cause more injury to creeping bentgrass and annual bluegrass when applied during hot weather, including liquid fertilizers, plant growth regulators, wetting agents, and even some fungicides. Labels on some products specify temperatures in which they should be applied. Use the break in the temperatures to apply products that may be needed.
5) Mowing and rolling. If you haven’t done it yet, raise the mowing height if you can, and roll a few days each week instead of mowing. Having more leaf area is always a good thing for the plant.