LDS or localized dry spot is a condition we encounter to some extent every summer in Macon / Warner Robins. Too often it is misdiagnosed as a “fungus” by an untrained eye. Fungicides are costly and a correct diagnosis should always be obtained by a qualified professional prior to application. Most fungus problems do not occur in drought conditions. If you are unsure what is causing a brown spot in the lawn part the grass back and feel the soil with your fingers. If it blows away like powder odds are there is not a fungus.
What causes localized dry spot? The most common causes we find are poor irrigation coverage. It’s important to understand that no irrigation system is perfect and it’s purpose is to supplement water in the absence of rainfall. Ideally heads should overlap each other and have adequate pressure. Rotors and spray heads should never be mixed.
What can you do if your sprinkler system is underperforming? Sprinkler systems truly need to be audited on a yearly basis. Parts wear out or break, nozzles get clogged, heads leak, etc. If you have a situation where you have different style heads on the same zone consider converting the fixed spray nozzles to rotary nozzles this will allow more uniform watering. Consider a smart controller like a Rachio, it uses weather data to calculate the soils moisture and only applies water when needed. It won’t run when there’s rain forecasted, when temperatures are below freezing, or when winds are too strong. Calibrate your sprinkler system. It’s not a good idea to set every zone for the same runtime. You have to consider the terrain. Are there slopes that tend to dry out? Are there swales that stay wet? Are there matures trees that hog the water? All of these things should be considered when programming the controller. Have a look at our post on watering if you’re still unsure about what to do.
Still seeing brown grass? In times of drought you may still see some dry areas appear even with a really well calibrated sprinkler system. If you just up the run times you will inevitably be overwatering some areas. To have even moisture in these cases it takes some hand watering. This is a chore so to maximize effectiveness consider using a hose end wetting agent. Here’s a link to a great product available on Amazon – Lesco Moisture Manager. Localized dry spot occurs when soil becomes hydrophobic. In these conditions the soil actually repels water so all of the the water you pour on with the hose can run right off. The addition of a wetting agent will reduce the surface tension and allow the soil to take up the water you apply.