Best Time To Weed and Feed Lawn

Your lawn is generally the centerpiece and the pride and joy of your garden, especially in the summer months when you can show it off to your family and friends.

You want it to be a healthy lawn that’s the envy of your neighbors— not one that’s full of weeds and balding of grass.

As soon as winter is over, it’s time to check out your lawn to see what damage has been done over the colder months. As spring arrives, your lawn should be starting to look back to its best.

If not, you will need to apply weed and feed to your lawn. This treatment will rid your grass of any unwanted weeds, and encourage new grass to grow.

Here, we’ll let you know when to apply weed and feed fertilizer to your lawn to get it looking vibrant and healthy in no time.

In this article we discuss:

  • What is Weed and Feed?
  • When to Weed and Feed Lawn – How Often to Apply?

What is Weed and Feed?

Weed and feed fertilizer is a universal name given to chemical products used to feed your grass and remove or prevent any weeds. This treatment strengthens your lawn and gives it the best start to the new season. The feed element of the treatment will also help with grass seed germination when overseeding your lawn.

It also makes your lawn more absorbent, allowing it to take in more water and nutrients than prior to the treatment.

Added vital nutrients from the feed will help your grass grow thick, strong and healthy. Your lawn will be a lush, vibrant green that you will want to show off.

Weed killer and feed products are available in gardening supply stores and are produced by many lawn care manufacturers. They generally come in a dry granular form or as a liquid that’s ready to use.

Weed Killer

The weed killer element in your weed and feed comprises various herbicides and is designed to rid your lawn of broadleaf weeds, dandelions, clovers, and many other green leafy weeds. The most common herbicides used are Dicamba, 2, 4-D and MCPP.


The feed component of the weed and feed are fertilizers that give your grass the nutrients it needs to grow thick and strong. These nutrients provide it with a healthy, attractive appearance.

The ingredients and blends of the feed will differ depending on the manufacturer. However, you will generally find a mixture of nitrogen, phosphorus and potassium.

The fertilizer is designed to help your grass flourish, assisting with new grass seed germination, and it will give it a head start into the new season.

Pre-Emergent Weed and Feed

As the name suggests, pre-emergent weed and feed products are used on your lawn before weeds appear.

These will create a barrier so that the weeds can’t grow, and it will feed your grass with much-needed fertilizers. However, it won’t kill existing grassy weeds in your lawn.

The pre-emergent treatment should be used once a year, at the start of the growing season in early spring. Doing this will tackle the weeds before they even appear on your lawn.

Post-Emergent Weed and Feed

Post-emergent weed and feed treatments are used to kill weeds that are already in your grass. The perfect mixture of chemicals will kill the weeds in your lawn and feed the grass with fertilizer.

Most post-emergent herbicides are recommended to be used several times per year. Mid-spring is the best time to initially apply it, then apply it again during the growing season.

It’s best to make the final application in the fall, as this will kill off any existing weeds and prevent them from reappearing the following spring.

Should I Cut My Grass Before Applying Weed and Feed?

Weed and feed can be a great addition to your lawn and will give fantastic results, but only if it’s used correctly. If you apply it at the wrong time or in unsuitable conditions, it won’t work and will waste both your time and money.

Many people ask if you should mow your grass and cut back the broadleaf weeds before applying weed and feed. The answer to this is no; you shouldn’t apply the weed feed straight after cutting your grass.

Mow your lawn a few days before using the treatment to the grass and wait for a few days after applying it before mowing again.

Give the weed killer and lawn feed time to work down through the leaves of the weeds and the grass and make its way to the roots. Once it’s absorbed throughout the weed and grass, it can get to work.

When you cut your grass following the treatment, you should make sure not to mow it too short or leave it too long, leave it about 3-5 inches.

Be mindful of the weather when you apply weed killers and lawn feed treatments to your grass. Ensure that rain isn’t forecast for a few days following the application.

Most weed and feed treatments require the grass to be kept dry for a couple of days after using it, to allow the weed and feed to be properly absorbed through the weed seeds. Rain dilutes the weed feed and won’t do the job that it’s supposed to.

If it does rain before the weed feed is fully absorbed, do not reapply it straight after. You won’t know how much was absorbed into the wet lawn, and,  if you use too much, the strong chemicals in the product could end up damaging your healthy lawn.  

When to Weed and Feed Lawn — How Often to Apply?

Applying weed and feed correctly is crucial, as the product contains strong chemicals. Therefore, you need to apply it to your grass only when it’s needed. Too much can damage and possibly even kill your lawn. Too little will have minimal, if any, effect on the weeds.

Pre-Emergent Weed and Feed

You should apply pre-emergent weed and feed before the weeds start to come through. The perfect time for application is early spring when the growing season is just starting.

Using it at this time, the soil will absorb the weed and feed to kill the weed seeds before they even get a chance to come through. It will also give your grass a great start to the season by making the roots strong and healthy and your grass lush and vibrant.

One treatment of pre-emergent weed and feed during the growing season of the grass should be sufficient.

You could, however, follow this up towards the end of the growing season in fall, with a treatment of post-emergent weed and feed. This will ensure that any weeds are killed before the winter season and give you a head start on the following year’s maintenance.

Post-Emergent Weed and Feed

If you’re applying post-emergent herbicides to your lawn, apply the first treatment in late spring. At this point, your grass will have started to grow, and any weeds will be coming through your grass. The product will absorb into the leaves and through the stalk of the weeds to the roots, perfect for broadleaf weed control.

If you apply the post-emergent weed and feed before this, for example, in early spring, it may miss some weeds that are just starting to grow.

Not getting all the weeds then means that you will have weeds growing straight after the weed and feed application. Applying another treatment to your lawn straight away may damage it,  so you will have to wait to get rid of any new weeds that come through.

Application in late spring means you will also be able to see the areas of your lawn that require the weed feed the most, and you can concentrate on these. This will ensure that the right areas of your grass will get completely covered with the weed and feed.

Your grass should be treated with post-emergent weed and feed twice a year to make sure that your lawn is at its best.

The second time you apply weed and feed should be at the end of the fall season to kill weeds remaining and give your lawn the pre-care it needs before winter. Your grass will then be weed-free, strong, and healthy in preparation for the winter season and the new year.

How To Spread Weed and Feed

There are different kinds of weed and feed available on the market—you can get it in granules or liquid form. With both types, there are some essential things that you need to consider before you apply the weed and feed to your lawn.

Make sure that you check the manufacturer’s instructions on the product so that you don’t miss out on any details specific to the product you’re using. The last thing you want to do is to ruin your lawn by not reading the instructions thoroughly.

Ensure that your grass is a suitable height before applying the weed and feed. You don’t want it to be too tall or not too short or it will affect how the product works. The best height for your grass would be around three to five inches.

Once you’ve got your grass at the correct height, wait between two to four days after mowing before applying the treatment. Waiting for the grass to grow slightly will protect your grass and make sure that the weeds are actively growing with new leaves appearing.

Be Safe

Take health and safety precautions when applying weed and feed. Make sure that you’re wearing gloves and long sleeves/trousers. The chemicals can irritate your skin, so you should cover up as much as possible.

If you have any children or pets at home, don’t let them near the garden when you’re applying the weed and feed. They should be kept away until the first rain has come to wash the excess away. If the weed and feed is ingested in any way, call 911.

Make sure that you don’t apply too much weed and feed to your lawn. You can always add more, but once it’s on, it’s almost impossible to remove.

Overuse will scorch your grass and damage it. If you do apply too much product, then try to flush it away by watering the area.

The weed and feed should be spread evenly across the lawn in an almost uniform manner. This ensures that every inch is covered and you end up with a stunning lawn wherever you’re looking.

When applying the product to your lawn, be careful not to apply it close to any plants, flowers or vegetables. It will kill these plants in the same way as it does the weeds. If you have to apply it close to these plants, maybe protect them with a plastic cover.

The grass should be left unwatered for around two to four days following the application. This is one reason why you shouldn’t apply the treatment during the hot summer months, as your lawn needs more water at this time.

Weed and Feed Is Strong Stuff

Weed and feed should only be applied twice each year as a maximum. More often than this, the chemicals within the treatment can damage your lawn.

Run-off is a result of over-applying the weed feed to your lawn. This is harmful to the environment and dangerous if it gets into local rivers, lakes or ponds. The feed element of the chemicals can promote and encourage algae blooms which are harmful to fish and native plants.


If you want a healthy lawn and your grass looking its best, it needs a little TLC. Applying weed and feed fertilizer will get rid of any weeds, and feed the grass to make it strong and healthy-looking, with a vibrant green appearance.

The chemicals in weed and feed products can be powerful, so make sure that you dress appropriately and follow the manufacturer’s instructions before using the treatment.

We hope you’ve found our guide informative and that you now understand the importance of correctly timing your application of weed and feed fertilizer to ensure the health and beauty of your lawn.

Weeds can be unsightly, and you don’t want to be sitting looking at them in your grass all through the summer.

Don’t forget other lawncare activities which will help your lawn to stay healthy, like dethatching when required, to keep it looking at its best.

If you take good care of your lawn, you will be rewarded with beautiful, luscious, healthy green grass that will be the envy of your neighbors and the talking point of friends and family.