Overwatering and Weeds
Weeds are present in every lawn, but by utilizing consistent, well-managed lawn practices, they are rarely a problem. Turfgrass that is over- or under-watered is often conducive to weed growth, but consistently overwatering will cause more damage. With appropriate watering practices, weed management is kept to a minimum, especially when partnered with proper fertilization and mowing implementation.
Overwatered lawns create the perfect conditions for certain types of weeds such as crabgrass and nutsedge to grow and thrive. Spreading crabgrass can greatly affect the growth of a lawn by limiting the amount of sunlight the grass receives. Excess water also promotes the formation of lawn fungi, most commonly Brown Patch Fungus.
For information on appropriate amounts of water to apply to your lawn in various conditions, please refer to the section of our blog entitled ‘Are You Watering Enough?’
Pre-emergent for Crabgrass and Other Summer Weeds
Crabgrass is one of the first grassy weeds to germinate in East Texas when the soil temperatures 2 inches deep reach 55 degrees Fahrenheit for at least 3 days in a row. In order to manage crabgrass, a pre-emergent is typically applied prior to germination in early spring, February to mid-March, and again prior to winter, generally in September, but varying from year to year.
A pre-emergent targets weeds that have not yet emerged from the soil and prevent the seeds from germinating. It forms a protective barrier to keep sprouting weeds from successfully reaching the surface while allowing established plants to continue growing. Crabgrass, goosegrass, Dallisgrass and grass burrs are among the early weeds managed with an early spring pre-emergent.
Brown Patch Damage
Brown Patch is a common fungal disease that causes large, dead circular areas on many lawns each year. It thrives in warm to hot temperatures and high humidity.
The best way to prevent Brown Patch is to keep your lawn as cool and dry as possible. Keep the turf mowed. Prune trees to allow more sunlight to hit the grass. A good watering every three days in the morning will allow the soil to stay dry as long as possible and keep the moisture away from the surface.
If the fungus does form, it can be treated with a fungicide. This will only prevent it from spreading. Mother Nature will take care of the rest when temperatures get below 40 degrees Fahrenheit to cause dormancy. Affected areas generally recover during regular spring turf growth.
For information on Brown Patch Fungus, please refer to the section of our blog entitled ‘Common Lawn Diseases.’
Rainfall and Pesticide Effectiveness
Addition of pesticides during unpredictable rain events can be challenging. Prolonged heavy rains can create concerns with pre-emergents not providing the desired length of expected weed control. Among the adverse influences on an herbicide application followed by extended heavy rainfall and soil saturation, are increased soil texture, decrease in organic matter, a decrease in the amount of turfgrass, herbicides moving from their intended area, and possible fungal activity.