When mowing during the summer, fescue usually performs best at a height of 2.5–3.5 inches. Never remove more than 1/3 of the leaf blade at a time. If you remove more than that, you will stress the grass and it may go brown for a short time. Taller blades provide more shade for your root system to stay cool and retain moisture during the hot summer days. If you are returning from vacation, you may have to mow multiple times to get the grass back to the desired height. Wait about 3–5 days between each mowing.
Do not overwater the grass. Fescue only needs about one inch of water weekly. Water for longer periods of time, less frequently and in the early morning hours. Take rainfall into consideration.
For optimal results, feed your lawn monthly during the summer season by applying the Lawnifi Summer Box liquid fertilizer program.
Check for and control white grubs in July and August. Treat with an insecticide if needed. If you use a granular variety, water the lawn immediately after application to help soil absorption. August is the best time to control grubs because they are small and feeding near the soil surface.
Fescue is highly susceptible to brown patch disease, which appears as irregularly shaped patches of dead or dying turf. Do not apply nitrogen fertilizer when the disease is active, keep the mowing height above three inches and water between 2:00–8:00 a.m. Apply a fungicide like Heritage G during severe brown patch outbreaks. If you use a granular fungicide variety, water the lawn immediately after application to help soil absorption.
Check for and control any white grubs, fall armyworms or sod webworms. Treat with an insecticide if needed. If you use a granular variety, water the lawn immediately after application to help soil absorption.
Apply fungicide if needed. If you have had a fungus or disease in your bluegrass in the past or have quite a bit of shade in the yard, apply a systemic fungicide to prevent future outbreaks. Consider mapping those areas because fungicide treatment can be expensive. If you use a granular variety, water the lawn immediately after application to help soil absorption.
Don’t make the mistake of mowing your fescue lawn too short. Keep your lawn between 2.5–3.5 inches in height with a rotary mower that has a sharpened blade. Never remove more than ⅓ of the leaf blade.
Don’t overwater. Fescue needs about 1 inch of water a week from natural rainfall or irrigation. If you apply any granular fertilizer or control product, you will need to water it in. This is a sufficient amount of water for the week. Overwatering may promote disease outbreak. Conduct an irrigation audit to evaluate how much water is being delivered to different areas of your lawn.
Apply a pre-emergent herbicide when soil temperatures reach 55 degrees Fahrenheit. This will prevent summer annual weeds like crabgrass, goosegrass and foxtail from plaguing your lawn and garden. Apply post-emergent herbicides in May as needed to control summer annual and perennial broadleaf weeds like white clover, knotweed, spurge and lespedeza. Products containing multiple broadleaf active ingredients are more effective in controlling broadleaf weeds.
Apply a broad-spectrum insecticide to prevent spring insects from appearing or to control any current spring insects like white grubs. White grubs may be active at this time. If you see any white grubs, apply a systemic insecticide.
Unlike warm season turfgrasses, there’s typically no real reason to make fungicide applications in the spring for fescue. If, however, you notice disease in your fescue, apply a systemic fungicide.