How to Use Preen in Vegetable Garden?

If you’re looking for an easy way to keep your vegetable garden healthy and thriving, look no further than Preen! This weed preventer is a great choice for organic gardens, and it can help improve the overall health of your plants. In this guide, we’ll answer some common questions about how to use Preen in your vegetable garden, as well as provide some helpful tips on getting the most out of this product. Let’s get started!

What is a Preen?

Preen is a brand of a weed preventer that is commonly used to control weeds in gardens and landscapes. The active ingredient in Preen is trifluralin, which is a herbicide that prevents weed seeds from germinating.

There is a Natural Preen option as well, the main ingredient there is corn gluten, which is a natural substance that still prevents weed growth just as well. It is safe to use around children and pets, and it will not harm your vegetables or other plants.

What is a Preen?

Preen works by coating the ground with a thin layer of herbicide. When weed seeds germinate, they send out roots that come into contact with the herbicide and are killed.

Preen comes in granular form. When applied with a broadcast spreader, the product can be easily and evenly coated over large areas to protect your lawn from. [1],[2],[7]

Uses of a Preen Weed Preventer

Being a pre-emergent herbicide, Preen is used to prevent weed seeds from germinating. You can use it around the perimeter of your house to prevent weeds from invading your flower beds, or in vegetable gardens to keep weeds from competing with your crops for nutrients.

Applying Preen before weeds emerge can help to prevent them from taking over your garden or landscape.
The best time to apply Preen is in early spring, before weeds start to germinate. For most areas of the country, this means late February or early March.

Differences Between Weed Preventer and Weed Killer

Preen is a weed preventer, not a weed killer. That means it prevents weeds from germinating and growing, rather than killing existing weeds. This is an important distinction to make because it changes the way you use Preen in your garden.

With a weedkiller, you would wait until you see weeds sprouting up and then apply the product to kill them. With Preen, you need to apply it before the weeds have a chance to germinate.

Preen also comes in different formulations for different uses. There is a general-purpose formulation that can be used around ornamentals, trees, and shrubs.

Weed killers, on the other hand, come in two types: selective and non-selective. Selective weed killers only kill certain types of weeds, while non-selective weed killers will kill any type of plant they come into contact with. They also leave unsightly dead plants in their wake.

Because weed killers are more aggressive, you will need to be more careful when using them around your garden. Even selective herbicides can harm your vegetables if you will use them in large quantities. [3], [4]

Is Preen Safe to Use in Vegetable Gardens?

Yes, Preen is safe to use in vegetable gardens when used as directed. The trifluralin used in Preen, only stops the germination of weed seeds. It will not harm existing vegetables, flowers, trees, or shrubs.

Preen can be applied around your vegetable garden as a precaution from weed invasion, or directly over the planting area before you sow seeds or transplant seedlings. Be sure to follow the product label instructions for best results.

While preen products are safe to use around established plants, they should not be used on newly seeded or sodded areas until after the seedlings have emerged.

Now that we know what Preen is and how to use it, let’s take a look at some tips for using Preen in your vegetable garden. [1],[5],[6],[7]

How to Use Preen in Your Garden

Applying Preen is easy, but it’s important to follow the product label instructions for best results.

Wear protective clothing

Preen is a herbicide and, as such, you should take care to avoid contact with your skin and clothes. Wear long pants, a long-sleeved shirt, gloves, and goggles when handling Preen products. If you do get Preen on your skin, wash the area immediately with soap and water. If you get it in your eyes, flush them out with water for 15 minutes.

Uproot all the weeds

Preen is most commonly used as a pre-emergent herbicide. This means that it is applied to the soil before weeds start growing. When used this way, Preen will prevent weed seeds from germinating. It will not kill existing weeds. For that reason, it’s important to remove all the weeds from your garden before you apply Preen.

Uproot all the weeds

To get rid of existing weeds, you can either pull them by hand or use a chemical herbicide. If you choose to use a chemical herbicide, make sure it is safe for the vegetables you are growing. You don’t want to accidently poison your food!

Once all the weeds are gone, you can move on to applying Preen.

Rake the soil

The next step is to rake the soil. This will help to loosen it up and make it easier for the Preen to penetrate. If you’re applying Preen to a large area, you may want to consider renting a power rake. This will save you a lot of time and energy.

Spread the granules

Now it’s time to apply the Preen. You can do this by simply shaking the bottle or using a munchkin. If you have a lot of ground to cover, you may want to use a fertilizer spreader. Whichever method you choose, be sure to evenly distribute the Preen granules over the entire garden. You don’t want to miss any spots or apply too much in one area.

You can use rake again to help spread the granules around and integrate in soil better, or you can just let them sit on top of the soil.

Sprinkle them with water

Once you’ve applied the Preen, it’s important to water it in. This will help to activate the herbicide and ensure that it works properly. A light sprinkling should be enough. You don’t want to wash away all of your hard work!

Wait before planting your vegetables

Now that you’ve applied Preen, you need to wait some time before planting your vegetables. This will give the herbicide time to work and prevent any seedlings from being killed.

Once the waiting period is over, you can go ahead and plant your vegetables. Be sure to follow the instructions on the seed packet or transplanting guide.

What to Keep in Mind When Using Preen

Preen is a great tool for keeping your vegetable garden free of weeds, but it’s important to use it correctly. Here are a few things you need to keep in mind when using it.

Don’t apply preen on seeds or young saplings

Preen works by stopping weed seeds from germinating. This means that if you apply it to your garden before planting, it will prevent your seeds from germinating as well. For this reason, you should only apply Preen after you’ve planted your seeds or saplings.

If you have young plants that are already growing in your garden, don’t worry – Preen won’t harm them. It’s only harmful to seeds that haven’t sprouted yet.

As long as your seedlings already have true leaves and are around 2-3 inches tall, it’s perfectly safe to use Preen around them.

Don’t disturb the soil after application

Once you’ve applied Preen, it’s important to leave the soil undisturbed. This means no tilling, hoeing, or raking. You also shouldn’t plant anything else in the area for at least a week.

Don't disturb the soil after application

If you disturb the soil after applying Preen, you run the risk of removing the herbicide from the top layer of soil where it needs to be. This can reduce its effectiveness and allow weed seeds to germinate.

Don’t use Preen on the flower soil

Preen is also harmful to flower seeds. If you want to use Preen in your garden, make sure to keep it away from the area where you’re growing flowers.

It won’t work on lawns

Preen is only effective on gardens – it won’t work on lawns. If you have a weed problem in your lawn, you’ll need to use a different product.

Lawns are made up of grasses, which have very different root systems from the weeds that grow in gardens. The roots of grasses are much deeper underground, so Preen can’t reach them.

If you apply Preen on existing grown weeds, it won’t kill them.

As you might have realized by now, if you’re using Preen to try and kill existing weeds, you’re out of luck. Preen only works as a preventative measure. It simply prevents weed seeds from germinating and growing in the first place.

This means that it should be applied to the soil before weed seeds have a chance to germinate. If you wait until after the weeds have already started growing, Preen will not be as effective.

If you have weeds, don’t worry, you can still get rid of them the old-fashioned way: by pulling them up and applying Preen afterwards.
Make sure to uproot them completely, including the root system, or they’ll just grow back. You can also use a hoe to loosen up the soil around the weed so that you can pull it up more easily.

It may not deal with all weed types

Preen is effective against most common garden weeds, but there are always exceptions. If you’re having trouble with a particular type of weed, it’s possible that Preen just won’t work on it.

Some types of weeds are resistant to herbicides, which means that even if you use Preen, they may still continue to grow in your garden.

It isn’t a permanent solution

Another thing to keep in mind is that Preen won’t work miracles. It will help reduce the amount of weeding you have to do, but it won’t completely eliminate weeds from your garden.

It isn't a permanent solution

Preen also won’t last forever. It only lasts for about one-three months, depending on the Preen type, so you’ll need to reapply it every few months to keep your garden weed-free. [5],[6],[7]


Can you use Preen around vegetables?

Yes, Preen can be used around vegetables. In fact, it is often recommended for use in vegetable gardens. Preen works by preventing weed seeds from germinating, so it can help to keep your vegetable garden free of weeds.

It is important to read the label carefully and follow the directions when using Preen, as it can also prevent some vegetables from germinating if used incorrectly. Some people also like to use mulch in their vegetable garden in addition to Preen. Mulch can help to suppress weeds and retain moisture in the soil.

Can you put Preen around tomato plants?

Yes, Preen can be used around tomato plants. However, it is important to note that Preen will not prevent blossom end rot, which is a common problem with tomatoes.

Preen can also be used around other types of vegetables, such as peppers and eggplants. It can help to keep these plants free of weeds and pests. While Preen is safe to use around most vegetables, you should always read the product label before using it in your garden.

How do I keep weeds out of my vegetable garden?

The best way to keep weeds out of your vegetable garden is to use a product called Preen. Preen is a pre-emergent herbicide that prevents weed seeds from germinating. It is safe to use around vegetables and will not harm them if used as directed.

Since Preen won’t deal with fully grown weeds, you’ll need to resort to another method. A great option would be a specialized weed killer that is safe to use around vegetables.

Can you use Preen and fertilizer at the same time?

Yes, you can use Preen and fertilizer together. However, you should always read the labels on both products to determine the best application method and timing for your particular vegetable garden.

Preen is a pre-emergent herbicide, which means it prevents weeds from germinating. Fertilizer provides nutrients that help plants grow. Therefore, it is important to apply Preen before weeds have a chance to sprout and compete with your vegetables for space and resources. It is also important to follow the directions on the fertilizer label so that you do not over-fertilize and damage your plants.

How long does Preen last?

Preen only provides weed control for up to three months. After that, you’ll need to reapply it or pull the weeds by hand. If you have a heavy weed problem, you may need to reapply Preen more often.

If you plan on using Organic Preen, keep in mind that it will last for only one month, which is much less than Treflan Preen does.

Useful Video: How to Use Preen Before Planting a Vegetable Garden : Vegetable Gardening


If you’re looking for a pre-emergent herbicide that is safe to use around your vegetable garden, look no further than Preen. Unlike weed killers, which kill everything in their path, Preen prevents the seeds from germinating so you can rest easy knowing your plants are safe from the weeds. Because of this however, you should apply it before planting any seeds.

Its instructions are fairly simple, just spread the granules on top of the surface, rake them in, and water well. Your veggie plants will thank you!