Can Weed Killer Be Used On New Grass?

Can Weed Killer Be Used On New Grass? Expert’s Review

Most of the time, weeds and grass grow together. Unwanted weeds prevent the new grass from extracting nutrition and moisture from the soil. Also, unnecessary weeds ruin the new grass shape and make them untidy.

So, Can weed killer be used on new grass?

No, you can’t use weed killers on fresh grass if the solution is chemical-based. It may harm the entire lawn and even kill the new grass. New grass doesn’t have a robust root system. If you have no other option but to use it, choose a safer option or be extremely careful while using it.

Here are more precise details on “Can weed killer be used on new grass?” Let’s dive in!

Can Weed Killer Be Used On New Grass?

Wide ranges of weed killer herbicides are available to kill different kinds of weeds. However, using weed killers on new grass may result in more damage than doing any good.

Types of Weed Killers

There are a lot of types. Let’s check some of them.

1. Pre-emergent Weed Killers

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Weeds germinate and produce seeds. When you use any weed killer before the germination of a particular weeds starts, this type of weed killer is called pre-emergent.

Instead of killing grown-up weeds, they mainly kill newly germinated weeds and sprouting weed seeds. Plus, they leave a residue on the soil, which remains inactive conditions for a considerable amount of time.

2. Post-emergent Weed Killers

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Pre-emergent herbicides kill existing weeds effectively. They are available in various types, such as selective or non-selective herbicides and systemic or contact herbicides. You can kill different kinds of weeds using weed killers such as dandelions.

3. Translocated or Contact Herbicides

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Weed killers are either come in translocated or contact forms. Contact herbicides kill only particular weeds that come with their direct contact. Alternatively, they hold back their growth.

On the other hand, Translocated herbicides travel to a particular spot with the help of transport systems (xylem or phloem) within the weeds. When you apply the solution to their leaves and foliage, it gradually moves to all parts of the plants from top to bottom. Finally, it will kill them.

Weed Killers in New Grass!!

Apply Weed Killers in New Grass

Grown-up grass and new grass are not the same. An established lawn has more endurance ability than new grass. Fresh grass is more vulnerable to becoming weak and damaged after applying weed killers. It can’t cope with the systemic weed killers that contain the main toxin ingredients.

Applying any pre-emergent will destroy the leftover grass seeds where the germination still has not started. It can also happen for the recently sprouting grass.

On the contrary, post-emergent weed killers can kill any new grass heavily, which has not still become grown-up. Hence, you should not use any weed killer on fresh grass unless it is specially made for the time of seedling.

How To Control Weeds in New Grass?

Many garden experts suggested not using weed killers on new grass until you have mowed it at least three times. If you see any weeds before the mowing, use your hands to root out them. This prevents them from growing bulky and harm grasses and plants.

Apart from removing weeds by hand, you should do extra work to protect the new grass and lawns. A grass’s vitality is primarily determined by water.

When the grass is new and small, deep watering is essential. Water it lightly so that it can reach up to 3 inches of upper soil. However, when it becomes grown-up, watering it heavily but intermittently is necessary. This makes the lawns healthy and makes their root system strong.

Remove Weeds before Planting Grass Seeds

Remove Weeds before Planting Grass Seeds

If you are planning to grow new grass, confirm the area is super clean. No weeds build up! Check out the spot clearly.

If you notice any weeds, kill them appropriately with a suitable weed killer based on its type. Using a post-emergent weed killer is better than a pre-emergent herbicide because it can kill the weeds right away. Plus, there is no active residue left on the area. Use glyphosate-based weed killers as they are powerful and don’t leave any residue after killing weeds.

On the contrary, if you use a pre-emergent herbicide, its active ingredients will stay on the spot for several weeks. It may harm the grass seeds.

If you notice the weeds have grown suddenly, something is fishy with the lawn. Taking immediate action is necessary. This mainly happens when you don’t take care of your lawn appropriately.

Weed can grow unnecessarily for several reasons:

Serial NoReasons
1Making the lawn excessively short
2Lack of nitrogen in the grass
3Inefficient water discharge system
4Watering lawns too much

How Do You Kill Weeds In New Grass?

You never know when and how weeds come on your lawn, even after taking all the precautions. Most of the time, they come through their reseeding process.

But the good news is that you can control these weeds as quickly as they come. Younger weeds are not as sturdy as established weeds. The quicker you remove them, the better it is.

Unfortunately, many new or even experienced gardeners use chemical-based weed killers to remove them. They end up harming or even destroying their entire lawn. Thus, you should always keep yourself out of systematic herbicides, such as Roundup, Weed & Feed, etc.

In case weed killers aren’t an option, maybe you’re wondering what you could use. When you recently sow grass seeds, weeds may come out between 6-8 weeks. If they don’t between these periods, controlling them seems easier. Just root out them.

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However, if the weeds are coming again even after hand pulling, you can use selective herbicide to deal with them. Over this time, the grass has already grown significantly. Since you are using only a selective weed killer, it will harm the grass if you apply it carefully.

But, cautiousness is extremely important when you are using too potent pesticides such as Roundup. If you think you can’t apply them precisely, choose a safer option that won’t harm grass. Otherwise, you will end up killing grass.

Before using the product, read the product label properly. If you don’t know how to apply it, take help from an expert or watch YouTube videos to have a clear idea.

So, the summary is that don’t use any chemical weed killers at the beginning. First, pull out the weeds manually. If they repeatedly come after pulling, use a systematic weed killer carefully.

When Can You Spray Weeds In A Newly Seeded Lawn?

New grasses are delicate and weak for the first few weeks. When one month passes, they start to become strong. You can use weed killers such as Tenacity, Quinclorac, etc., on the new grass after passing 28-30 days. However, applying weed killers after two-time mowing sessions is a solid rule of thumb.

How to Prevent Weeds in New Grass?

How to Prevent Weeds in New Grass?

Completely preventing weeds may not be possible. But it is important to take every precaution possible. The best option you can apply is to choose the perfect lawn timing.

Most garden experts agree that “late summer to early fall” is an ideal period to seed a new lawn. However, each location will have a different outcome.

Choose a perfect timing when the soil is enough but not excessively worm (like summer season). As you already know, high temperature doesn’t encourage healthy growth for grass. During this season, grass overgrows, and they develop root systems.

If you fail to saw grass seeds during this period, your second choice should be early spring. But choosing this period requires you to take some extra precautions.

5 Pro Tips to Prevent Weeds on New Grass

1. Choose quality seeds

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The better the grass seeds, the more healthy and sturdy will be the new grass. Make sure the seeds don’t contain any weed seeds. Read the packaging level properly whether there are any other seeds or not.

2. Mulch the Area

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Mulching the lawn will prevent the weeds from overgrowing. Make sure you choose the ideal mulch and the suitable materials to support the new grass. Avoid using hay mulch. They cause contamination.

3. Water & Feed

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Watering and feeding the new grass is necessary. You should water the fresh grass regularly and make sure it reaches around 6 to 8 inches of the ground. Additionally, use high-quality soil to provide enough nutrition.

4. Don’t Mow Early & Overly

Don't Mow Early & Overly

Following perfect timing to mow the new grass is crucial. Wait at least six weeks to cut the new grass. In addition, don’t mow the fresh grass too short. It may make them weaker and restrict their nutrition supply.

5. Reduce watering

When the new grass becomes is appropriately established, you don’t need to water it every day. Established lawns don’t need as much water as new lawns do. Otherwise, you may end up overwatering them.

Wrapping Up

Controlling weeds for new grass is essential. They may eat up all the nutrition from the soil and make the new grass shabby. Take enough care of your new lawn, and follow our pro tips to prevent weeds on fresh grass. Hopefully, the answer to the question “Can weed killer be used on new grass?” is clear from the previous section.

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