By Glenda Taylor | Published Jul 28, 2022 12:00 PM

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Pulling weeds is a lot of fun, said no one, ever. But if neglected, weeds can spread rapidly, choking out desirable plants, sucking vital nutrients from the soil, and blocking the sun and air flowers need to develop beautiful blooms. While many types of herbicides line garden center shelves, finding the right weed killer for flower beds needn’t be confusing.

Rather than buying a product at random and hoping it wallops weeds—without destroying desirable plants in the process—take a few minutes to check out this weed-killer guide. Learn what to consider when shopping for the best weed killer for flower beds, and find out why the following products are among the top options for keeping flower beds weed-free.

Anyone who reads the fine print on labels will find that commercial weed killers come with a rather stern warning: It’s a violation of Federal law to use this product in a manner inconsistent with its labeling. This is because many weed killers contain toxic chemicals that can harm humans, pets, and/or the environment if not applied correctly. Using these products in a safe, responsible manner is essential. Consider the following when shopping for a weed killer.

Weed killers come in two primary types: selective and nonselective.

This distinction refers to whether existing weeds need to be destroyed, or if the gardener hopes to prevent them from taking root in the first place.

Nonselective herbicides—the ones designed to kill all plants—are also classified as either contact or systemic. However, these terms don’t always appear on product labels.

In general, chemical weed killers are more dangerous to humans, animals, and the environment than natural weed killers. Unfortunately, chemical weed killers are often more effective than natural versions, such as products that contain salt or vinegar. For example, it’s usually necessary to apply a single dose of chemical herbicide that contains glyphosate, while users may need to apply a natural herbicide two or more times to kill the weeds, depending on the strength of the product.

While some gardeners will DIY their own effective natural weed killer by creating a vinegar, salt, and dish soap solution, a commercial product does offer grab-and-spray convenience.

However, no weed-killing product, even a natural one, is completely harmless because accidental overspray may kill desirable plants. Plus, some all-natural products may irritate the skin of humans sensitive to the ingredients. So while natural products are less harmful overall, it’s imperative to follow the application instructions of any herbicide carefully.

Application methods will vary based on the type of weed killer selected.

It was quite a quest to find the best weed killer for flower beds that won’t kill flowers! The products described here all contain ingredients known for killing weeds or for keeping weed seeds from sprouting. They’re effective and relatively straightforward to use. Still, weed-killing needs vary from gardener to gardener, so we’ve included a variety of herbicide types, both organic and chemical, including post- and pre-emergent products. Each is a standout in its category.

Home gardeners and landscapers who’ve already planted their flower beds and want to keep new weeds out should check out Preen Garden Weed Preventer. The nonselective granular formula is simple to use: Sprinkle around the base of desirable plants and over bare soil in a flower bed, then water lightly, which encourages the granules to dissolve and form a barrier.

Users can also sprinkle Preen over mulch, such as shredded bark or pea gravel, and it will dissolve to form a barrier that prevents weed seeds from sprouting. Be aware it will also stop desirable seeds from sprouting, so don’t apply it if you plan to sow flower seeds.

Preen comes in a jug with a shaker-type applicator top so there’s no additional spreader to purchase. The chemical formula will work continuously for up to 3 months, after which it can be reapplied. However, this pre-emergent herbicide will not kill existing weeds, if any have already taken root; use a post-emergent product or pull by hand before treating the bed with Preen.

Get the Preen 2464110 weed killer for flower beds at Amazon, The Home Depot, or Lowe’s.

To banish weeds in and around flower beds in a way that’s economically—and ecologically— sound, consider Harris Vinegar Weed and Grass Killer. It features concentrated acetic acid (vinegar) as its active ingredient. This affordably priced weed killer comes in a 1-gallon jug and includes a spray trigger on a hose that connects to the jug for applying the product directly to the offending weeds.

This nonselective weed killer should be sprayed liberally on unwanted weeds, but don’t let overspray come into contact with desirable flowers. If necessary, consider shielding those pretty posies with plastic film during application to protect them, removing the plastic after the solution has dried.

Get the Harris weed killer for flower beds on Amazon or at Tractor Supply Co.

Any gardener concerned about overspray inadvertently harming prized flowers might wish to use Ortho Grass B Gon Weed and Grass Killer. This selective chemical weed killer specifically targets invasive grasses, including crabgrass, sandbur, bentgrass, and more—without harming ornamentals.

Many types of grass can be vanquished with a single application of post-emergent, Ortho Grass B Gon, but hard-to-kill weedy species, such crabgrass and Bermuda grass, may require a second application 7 days after the first. The product comes in a bottle with an attached trigger sprayer, and no dilution or mixing is necessary. Take care not to let overspray get on lawns, where it will likely kill the grass.

Get the Ortho weed killer for flower beds at Ace Hardware or The Home Depot.

Short on flower-tending time? Consider using a long-lasting product, such as Preen Extended Control Weed Preventer, that stops new weed seeds from sprouting for up to 6 months. This pre-emergent herbicide works by forming a chemical barrier at the soil level that prevents seeds from germinating.

Inside the container of this granular herbicide, users will find an applicator scoop featuring dozens of tiny holes that help disperse the product uniformly. The product can be used on bare soil or in conjunction with mulch, such as shredded bark or rubber chips. Apply only around established flowers and nonedible ornamentals. This specific Preen product is not intended for use around fruit and vegetable plants.

Get the Preen 246244 weed killer for flower beds on Amazon or at Lowe’s.

Natural Armor Weed and Grass Killer is a nonselective, post-emergent herbicide formulated to kill any weeds that dare encroach on flower beds. The natural product is an optimal choice for edging along the borders of a flower bed to create a sharp look, but it can also be used on weeds growing in the bed itself.

Natural Armor comes in a 1-gallon jug and is ready to use—no mixing or diluting necessary. Unfortunately, a sprayer is not included; users must purchase one that connects to the jug top or use the solution in a hand sprayer or a pump-type garden sprayer. For best results, weeds should be thoroughly saturated. Keep in mind that this is a nonselective weed killer, so take care not to allow overspray to get on desirable plants.

Get the Natural Armor weed killer for flower beds on Amazon or at The Home Depot.

Like all Preen weed preventers, this pre-emergent product stops weed seeds from sprouting, but this one also provides a well-balanced dose of fertilizer to help plants grow well and develop a healthy root structure. Preen Plant Food Garden Weed Preventer contains nitrogen, phosphate, potash, and sulfur to boost plant health.

This nonselective chemical product comes in granular form and is easy to apply with a shaker lid for fuss-free, uniform application. A single application will feed plants and keep weed seeds from sprouting for up to 3 months. It can be used on bare soil or in conjunction with mulch, such as shredded bark or pea gravel. It should only be used where plants are already established. Seeds of desirable plants will not sprout if sown in soil that’s been treated with a pre-emergent.

Get the Preen 2164116 on Amazon or at The Home Depot.

The active weed-killing ingredient in this herbicide product is acetic acid—or vinegar, as it’s commonly known—plus some essential oil and citrus to give it a pleasing smell. It’s safe for both pets and the environment, but as a nonselective weed killer, it can harm desirable plants, so apply with care.

The liquid is ready to use, with no mixing or dilution required. There’s no included sprayer, however, so users must pour the liquid into a trigger-type hand sprayer or use a pump-type garden sprayer. For the best results, saturate weeds thoroughly and allow the product to dry completely before letting pets play in the area.

Get the Just For Pets weed killer for flower beds on Amazon.

All of the weed killers in this lineup are among the top options for killing existing weeds in flower beds or for keeping new ones from growing, but our best overall pick, Preen Garden Weed Preventer truly stands out. It’s a pre-emergent that keeps weed seeds from sprouting, and it protects flower beds for up to 3 months. Our budget pick, Harris Vinegar Weed and Grass Killer, is an all-natural product that destroys existing weeds yet won’t leave toxic residue in the soil.

We extensively researched dozens of herbicides when selecting the best weed killers for this lineup. While we took popular brands into consideration—Preen and Ortho are nationally known manufacturers of quality gardening products—we didn’t automatically eliminate products from smaller or niche manufacturers if they contained the ingredients necessary for killing weeds.

We chose a variety of both selective and nonselective herbicides, as well as several pre-emergent products to satisfy the needs of different gardeners—there’s simply no one-size-fits-all product that’s suitable for all flower beds. We didn’t exclude all chemical weed killers but we gave preference to natural and less toxic synthetic products.

Flower beds are at their most striking when they’re full of beautiful blooms—not weeds. Gardeners are always free to use the time-honored tradition of hand-weeding, but for those who’d like a little assistance, herbicides can help. Those who are new to cultivating flowers are likely to have a few questions.

You can’t completely weed-proof a flower bed. However, you can greatly reduce the number of weeds by applying a pre-emergent herbicide to the bed once desirable plants are established but before weeds sneak in.

Unwanted weeds compete for vital nutrients that ornamental plants need to produce large, colorful blooms. Plus, a weedy flower bed simply looks sloppy.

A selective weed killer that targets just grasses is one of the best ways to stop grass invasion without harming your flowers.

Only if the weed killer is a selective product designed not to harm plants. If it’s nonselective, it will kill beneficial plants as well as weeds.

Yes, and they’re better for the environment. In some cases, however, they may not be as strong as chemical weed killers, and users may need to use more than one application.

It varies. Follow the application instructions carefully. Many weed killers list a certain amount of time that must elapse before allowing pets to play in a treated area. In general, natural weed killers are safer than chemical-based weed killers.

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