Why Crabgrass Keeps Coming Back, and What Spot Spraying Does

You pulled it in June. You mowed over it in July. By August it is back, wider than before, and flat against the ground where the mower blade passes right over it. If that sounds familiar, you are not doing anything wrong. Crabgrass is built to win that particular fight, and understanding how it works makes it much easier to deal with.

A weed that plants next year's crop before it dies

Crabgrass is an annual. Each plant lives for a single season, then dies at the first hard frost. What it leaves behind is seed, and a mature plant can drop a great many of them. Those seeds sit in the soil all winter. When the ground warms up in spring, they sprout.

That is why a lawn that looks clean in November is not a lawn that is clean. The dead plants are gone, but next year's seed is already in the dirt waiting for warm soil and a bit of sunlight.

Why some lawns get it worse

Crabgrass seed needs light to get going. A thick, healthy lawn shades the soil surface, and most seeds that land in it never get a real start. A thin lawn leaves the ground open, and the seeds make the most of it.

• Thin or bare patches, especially after a dry stretch or a rough summer.
• Turf cut very short, which lets sun reach the soil.
• The hot edges of driveways, sidewalks and curbs, where pavement bakes the soil.
• Compacted ground, where grass roots struggle but crabgrass does not.
• Soil conditions that keep the lawn weak, including a pH that is off.

In other words, crabgrass is as much a symptom as a pest. It tells you where the turf is thin.

Preventing it and reacting to it are two different jobs

The standard approach is to stop seeds from sprouting. A preventer goes down before germination, so it has to be timed to the soil warming up, and timing is the whole game. It does nothing to plants that are already up. Miss the window and you are in the second job, which is dealing with what has already sprouted.

The right mix depends on your grass type, your yard and the season. That is why it is worth asking whoever treats your lawn how they handle crabgrass and when, rather than assuming it is covered.

What spot spraying does

Spot spraying means going after the crabgrass plants that came up instead of treating every square foot again. It is a targeted pass: find the patches, treat the patches.

Customers notice it. Jimmy Allen wrote in a Google review after switching to EverGreen: “Justin came out to give me a quote and was very thorough with what our yard needed. They were out within a few days getting it treated and the crabgrass spot sprayed.”

Spot spraying is also honest about what it can and cannot do. It clears the plants you can see. It does not change why they grew there. A dead patch of crabgrass leaves bare soil, and bare soil is an invitation. If nothing thickens that area, the same spot will sprout again next year.

What actually thins crabgrass out over time

A lawn that is fed properly, has its soil pH looked after and is not cut too short is a lawn that shades its own soil. EverGreen's lawn treatment includes fertilization, weed control and lime application to correct soil pH, and one customer's Google review mentions aeration as well. Those pieces work on the cause, while spot spraying works on the symptom. You want both.

If you mow your own lawn, a few habits help right now:

• Mow a little higher. Taller grass shades the soil and gives seed less light.
• Water deeply and less often, so roots go down and the surface does not stay constantly damp.
• Pull small plants early if you like, ideally before they set seed, and bag them instead of leaving the pulled plants on the lawn.
• Watch the edges along pavement. They are usually where it starts.

Call when you first see it

The best time to call about crabgrass is when you first spot a few plants, not when the whole front yard has gone to seed. Small and scattered is easy to treat. Big and mature is a long season of trying to catch up, and a fall full of seed for next year.

EverGreen Lawns & Pest Control serves Springdale, Fayetteville, Rogers, Bentonville and the rest of Northwest Arkansas. Read more about the lawn side of the business on the Lawn Treatment page, or call (479) 231-7477.