7) What are pre-emergent and post-emergent weed killers?

7) How we choose the best ice cube trays

Crabgrass control starts with knowing what you're dealing with and when to step in. Most weed control products fall into two categories: pre-emergent and post-emergent. Each one targets crabgrass at a different stage, so using the right type at the right time can make or break your results.

Pre-emergent herbicides are all about prevention. They create a barrier in the soil that keeps crabgrass seeds from germinating. Timing matters here. You need to get the product down before the soil warms up too much, usually when it hits around 55° for several days in a row. These products won't do anything for weeds that have already broken through, but they're one of the best ways to stop a crabgrass problem before it starts.

Post-emergents take care of weeds that are already growing. They get absorbed through the leaves and start breaking the plant down from the inside. This is the option to reach for once crabgrass is already showing up in patches. Spot treatments fall under this category too. They let you zero in on problem areas without damaging the rest of your lawn. These are especially useful for sidewalks, garden edges and any place where precision matters. Knowing how and when each of these works can help you pick the right tool for your lawn's condition.

8) How we chose crabgrass killers

To narrow down the best crabgrass killers, I focused on products that meet the needs of real lawns, whether you're doing early-season prevention or trying to get a handle on a full-blown weed problem. I prioritized formulas that specifically target crabgrass, either by stopping seeds before they sprout or by killing the weeds once they're up. I also looked at how easy each product is to apply, how safe it is for your grass and garden beds and how long the results last.

Some of these picks were tested firsthand in lawn conditions, while others were selected based on strong brand history and performance in past Good Housekeeping Institute evaluations. I leaned on years of product testing and insights from lawn care pros to help separate what works from what just takes up space in the shed. Companies with a clear label, solid instructions, and consistent results earned their spot.

I also made sure to include different formats for different comfort levels. That means ready-to-use sprays that are designed to kill weeds after they've sprouted (post-emergent), granular preventers that are used to kill weeds before they've appeared (pre-emergent), and more selective options for tight spots. Whether you're trying to keep your lawn looking sharp or reclaim it from a crabgrass invasion, these products cover the bases.

9) What to look for when shopping for the best crabgrass killer

You can tell from this list that not all crabgrass killers are built the same, and picking the wrong one can mean wasted time, money and effort. Whether you're treating your whole lawn or just hitting a few weedy spots, it helps to understand what makes a product effective and worth your money.

✔️ Type of herbicide: Know whether you're looking for a pre-emergent to stop seeds before they sprout or a post-emergent to kill what’s already growing. Some products combine both, but most are designed for one specific purpose.

✔️ Grass compatibility: Always check the label to make sure the product is safe for your specific grass type. Some formulas are fine for most cool- or warm-season grasses, while others can damage certain varieties.

✔️ Application method: Crabgrass killers come in granular form, trigger sprays, ready-to-spray hose bottles and concentrates. Choose what suits your comfort level and the size of the job. Spot treatments are best for small areas. Granules and hose-end options work better for full-lawn coverage.

✔️ Rainfast time: If you live in an area where surprise rain is common, look for a product that becomes rainproof quickly. That can make the difference between a wasted application and lasting results.

✔️ Coverage area: Make sure the product you choose matches the size of your lawn or the area you need to treat. Overshooting or undershooting can lead to poor results or wasted product.

✔️ Extra benefits: Some formulas include added fertilizer or extended weed control. These can be useful if you're already planning seasonal lawn maintenance and want fewer steps.

✔️ Safety around people and pets: If you have kids or animals playing in the yard, look for crabgrass killers labeled safe for use around people and pets when applied as directed.