When To Apply Dimension Pre-Emergent

Preventing a problem before it becomes an issue is better than trying to tackle an issue after it has become a problem.

One of the ways we can do this in lawns is by applying pre-emergents.

Pre-emergents are a form of herbicide. Pre-emergents contain chemicals used to prevent certain plants from growing. They do not control plants that have already emerged; hence they are called PRE-emergents.

These products are only used to control plants or weeds BEFORE they take root. Therefore these are used to prevent a problem and not try to fix one.

Pre-emergents work by inhibiting the enzymes within a germinating seed and stunting and stopping its growth. Also, these pre-emergent herbicides work to isolate a seed from any surrounding nutrients that facilitate growth.

These are often used with crops to keep weeds from growing and leeching the nutrients from the plants. For our purposes, though, we are going to be discussing the use of pre-emergents in lawns and gardens.

A typical application for pre-emergents in both lawns and gardens is in the spring before weeds have had a chance to germinate. This will help control summer weeds like crabgrass, goosegrass, foxtail, and several broadleaf weeds.

If you know your lawn or garden struggles against winter and fall weeds, you may also want to apply a pre-emergent in the fall.


One of the tricks to the successful use of a pre-emergent is to apply it before the weeds germinate and not when the healthy grass that you want is trying to grow. It can be difficult to time when to put it down.

Each product has its own area of expertise, you could say. Meaning that different per-emergents are made to take on different weeds. So, when you’re looking for a pre-emergent for your yard, you will want to check to the label to see if that product will deal with the weeds you have.

One of the many pre-emergents on the market today is Dimension Pre-Emergent.

This particular pre-emergent will fight against your common summertime weeds:

  • crabgrass
  • goosegrass
  • foxtail
  • other annual grasses,
  • broadleaf weeds.

It is safe to use on garden plants, decorative plants, yards, gardens, commercial sod farms, and golf courses.

For granular – use a spreader to put it down (avoid getting pre-emergent that is combined with fertilizer…it confuses the good plants).

For small areas, you can use a hand-held spreader. If the area is larger, you will likely want to use a push spreader or maybe even a tow-behind model. The same rotary spreader you use for applying fertilizers and such will work great for this as well.

Though, if you use a rotary spreader, you will have to be more aware of where the granules are going than if you use a drop spreader.

You do not need to cover the ground completely; give the ground a consistent dispersed covering.

For liquid – either in a premixed bottle that can be attached to a hose or will need to be mixed into a sprayer tank. Though convenient, this method does have still needs to be washed into the soil and off the leaves, or it will be useless.

No matter what product version you use, you will need to make sure that you run water over it to get it into the soil and allow it to work its magic.

So, the burning question is, when should you apply Dimension Pre-Emergent?


This is a product that will work better the earlier you apply it. However, you don’t want to put it down too soon. So, the best time to put down pre-emergent is in the early spring. That way, you catch those early weeds before they go to seed and start causing problems.

Just remember, earlier is better. Though, I must add a side note; an early application may miss some of the weeds that germinate later in the season. To solve this issue, you can reapply a few weeks later to make sure you’re getting those late bloomers as well.

Eventually, you will learn how your yard acts and the various growth cycles of weeds. This will help you balance when you should apply an early pre-emergent so you don’t miss the late bloomers.

Essentially, there is no exact time that you should apply pre-emergent. It’s all based on your individual lawn. However, you can test a few things to see if your yard is ready to start growing the weeds you want to curtail.

You can test the soil temperature. Most weeds won’t grow if the winter frost is still lingering in the soil. So, you’ll want to use a soil testing thermometer or another temperature gauge to test the soil temps.

The temperature that different weeds grow varies across regions. This makes offering a specific temperature to apply pre-emergent difficult to say. I’d suggest checking your local and/or state data for expected emergent dates for common weeds in your area.

You can also test how moist your soil is. Again, this is to determine if your soil is fit to start growing those pesky weeds. If your soil is too dry or too wet, the weeds won’t grow. So, you will want to make sure that the soil is just damp before you spread pre-emergent.


You will also want to apply pre-emergent in the fall to prevent winter weeds from growing and potentially take on the really early spring weeds.

In the south, if you spread pre-emergent in late fall or early winter, you will protect your lawn against early January and February crabgrass emergence. Because most northern states are so cold in the winter or covered in snow, there aren’t any winter weeds to worry about.

Unless you know you have winter weed problems, the only reason to spread pre-emergent in the fall is to prevent early spring weeds from germinating.

Again, the key is to learn your lawn and learn when your weeds start to become a problem. The more you know, the more accurately you can time your pre-emergent application.