Dense, deep green grass blades are a hallmark of healthy fescue (Festuca spp.) gras. You can sink your bare feet into this grass on a warm spring day. But recently seeded fescue needs some time to grow before it creates the thick grass necessary for safe mowing. Along with the ideal time, you want to decrease fescue to the ideal height to stop damaging the blades and turning the yard yellow.
Waiting Game
Although immature fescue origins hold tightly to the ground below, your lawnmower’s weight easily damages sensitive seedling stems and shallow root systems. It is good practice to allow the new fescue to grow to at 6 inches tall before you perform any mowing. This allows the roots time to set up and to get the stems to adult. The grass grows quickly during warmer weather in fall and spring, but grows more slowly in the warmth of the summer.
Cutting Length
Maintaining the fescue grass at 6 inches turns your yard into a jungle, but you should not cut the grass down to 2 or 3 inches to the initial cut. Fescue needs weekly trimming, removing one-third of the grass’s height at each mowing. By trimming the grass blades slowly, you maintain the plant’s knife structure to get healthier photosynthesis.
Ideal Cool Weather Blade Length
When you establish a mowing program, keep the new fescue 2 1/2 inches tall throughout spring, fall and winter. This height allows rainfall to penetrate down into the ground for appropriate saturation. Fescue likes a deep watering of up to 6 inches so roots grow deeper in the soil for moisture. Deep watering also prevents disease that proliferates with moist conditions, like fungus. If you wait till the grass gets to 3 3/4 ins, then you can cut the blades to two-thirds of their height, or 2 1/2 inches.
Warm Weather Factors
Let fescue grow slightly taller in summer. By cutting the grass to 3 1/2 ins, then you create a shaded area beneath each blade. Weed seeds find it difficult to germinate in dense shade, which maintains the yard looking tidy. Any weed seeds that do germinate often die from lack of nutrients, water and light. Suffocating weeds with more fescue grass means you’ll have less weed-pulling and won’t need to use weed killers.