Professional Lawn Fertilization & Weed Control in McLean, Virginia

Pre-emergent crabgrass control needs to go down before crabgrass seeds germinate, which happens once soil temperature holds 50-55°F for several consecutive days at a 2-inch depth. In Fairfax, Loudoun, and the greater NoVA area, that typically falls in mid-to-late March, though it can shift a few weeks earlier or later depending on the spring. We track local soil temperatures rather than a fixed calendar date, and it's always better to apply a little early than to miss the window — once crabgrass has germinated, pre-emergent products won't stop it.

Yes. Our applicators are licensed and use products applied at label-directed rates, and we recommend keeping kids and pets off treated turf until it dries, generally a few hours. We'll flag any specific waiting period for a given application and can time visits around your household's schedule if needed.

We strongly recommend it, and include one at program start. Because Northern Virginia's clay soils are frequently acidic, a soil test tells us your exact pH and nutrient levels so we only apply lime or specific amendments your lawn actually needs, rather than guessing. It's the single biggest factor in whether a fertilization program delivers visible results.

When soil temperatures hold around 55°F for several days — typically mid-March to mid-April here. We track soil temperature rather than picking a date, because a warm spring can move the window up two weeks. Our crews work McLean regularly, so scheduling is usually available within the week outside the spring rush — and every visit ends with before-and-after photos of the finished work.

We apply at label rates with licensed technicians and give you a simple re-entry window after each application — usually once the product has dried. We'll flag every visit in advance so you can plan yard time around it. Our crews work McLean regularly, so scheduling is usually available within the week outside the spring rush — and every visit ends with before-and-after photos of the finished work.

Most Northern Virginia homeowners pay roughly $50-$105 per visit, or about $250-$600 for a full 5-7 round annual program, depending on lot size, current lawn condition, and whether lime or extra weed treatments are needed. Lawn Theory's seasonal programs start around $199/month and scale up based on square footage — we provide a written quote after seeing your property so pricing is never a guess.

The most common cause is soil pH. Northern Virginia's clay soils often test between 5.0 and 6.0, but cool-season turf needs roughly 6.2-7.0 to actually absorb the nutrients in fertilizer. If pH is too low, applying more fertilizer won't help — the nutrients stay locked in the soil. A soil test identifies whether lime is needed to correct pH before further feeding does any good.