Is your lawn type cool-season (fescue, ryegrass, or bluegrass) or warm-season (zoysia)? Both are growing right now, so it's hard to tell from the photo alone, though cool-season grasses are slowing and going summer-dormant soon, during which time a moderate amount of browning is normal and unavoidable.

When to fertilize will depend on the grass type, as nutrient supplementation might improve grass color a bit. What formulation to use, and in what dosage, will also depend on the results of your most recent laboratory soil test, in order to comply with Maryland lawn fertilizer restrictions. If nitrogen, iron, manganese, or magnesium were deficient, for example, a boost in any of those nutrients can green-up a lawn. Nitrogen is not part of a standard soil test, since such measurements would not be very reliable, but it's a component in all lawn fertilizers anyway.

Yellowing and browning can also occur with a range of commonplace turfgrass diseases. Even if not actively spreading or worsening now, several fungal pathogens can cause damage to grass blades, making a lawn overall look less green. Many of these do not require fungicide intervention (which can't cure existing infections anyway, just suppress new ones), and the grass will grow out of the damage in due time. (For example, cool-season grasses, when they resume more active growth in autumn, will look better on their own, compared to their normal stagnation in growth for summer.) You can explore our Lawn Diseases information if you want to see if symptoms match certain conditions; close examination of leaf lesions might be needed to tell one infection apart from another.

Drought stress can also shut down growth and cause some grass blades to shrivel and turn yellow or brown. While occasional watering helps reduce heat stress on cool-season grasses, and supports good zoysia growth, over-watering will encourage infection spread and will not necessarily keep cool-season grasses in active growth all summer. Our mid-Atlantic conditions make it challenging to have a lawn thrive all year long with no interruptions in growth or a lush appearance.

Miri

Thank you for the reply. It is tall type turf fescue.

Okay, then the turf may be starting to go dormant for the summer, given our recent heat and dry conditions. If a fungicide regimen is already being used, then no other intervention for fungal diseases should be needed at this point. Keep an eye on watering needs so the browning doesn't become too extensive (the turf roots should stay alive, even if drought kills some foliage), and any minor fungal outbreaks should resolve themselves and you can fertilize as normal later this autumn.

Miri

Is the lawn being watered intermittently, only when the soil about four inches deep feels somewhat dry to the touch? If watered too lightly (for too brief a duration), the soil in the root zone won't get damp enough to keep the grass hydrated, and if watered too often, the frequent leaf wetness will encourage fungal outbreaks, even in the presence of fungicide applications. Our Watering Lawns web page provides guidance. Lawns should get greener, if they chance color at all, after watering, if they were getting too dry; if they are too wet, yellowing might indicate root stress or dieback. The lawn pictured actually looks pretty good for early summer (it's dense, and there isn't heavy browning), and looks fairly typical of tall fescue once it gets hot and less rainy than it was in spring, as we're experiencing now.

Miri

Thank you for answering my questions. I feel so much better now! Have a great weekend!

You're welcome!