Do Pre-Emergents Stop Dandelions?

Do Pre-Emergents Stop Dandelions?

Dandelions may add some brilliant color to your lawn, but they can be as stubborn as crabgrass or any other weed. Their deep tap roots make them pretty difficult to get rid of. However, they are not too difficult for pre-emergents to handle.

Pre-emergent herbicides have proven to be a lifesaver on numerous occasions. They can literally stop dandelions in their tracks, and they are also very effective in the control of various types of weeds.

The most important thing to keep in mind however is that controlling dandelions with pre-emergent alone will take several years and that’s because the dandelions you see every Spring and Fall are either the result of a new seed germinating or an old plant underground sending up new top growth.

Because dandelions are perennials, pre-emergents will only stop the new plants from establishing themselves in the lawn and over the following years the existing dandelions will slowly die as their lifecycle (typically a few years) comes to a natural end.

NOTE – Because dandelions can sprout at very wide soil temperature intervals it is advisable to use a long lasting pre-emergent (PE) to stop the spread of new plants in the lawn. Prodiamine at full strength should give you good coverage for roughly 5 months. If applied in March and again in August you should prevent the growth of almost all new dandelions for the entire year. Other types of PE have different lengths of effectiveness. You can see more about the alternatives here.

What Are Dandelions

Dandelion is a class of herb with European origin. The most common species is Taraxacum officinale. It is a plant with pretty bright yellow flowers. Although it has European origin, it grows in most parts of the world.

I know you probably want to get rid of the dandelion in your lawn, but you’ve got to know that not everyone considers it to be a weed. Dandelions are very medicinal. As a matter of fact, a lot of folks use their leaves and flowers for various healing needs. I even made a full video on why you might not want to kill them in the first place.

Nonetheless, I didn’t write this article to convince you to keep dandelions scattered around your lawn. They can be pretty annoying; at least, I’ve experienced their annoyingness first hand. They’ve got very potent taproots than can grow even if you cut off the plant at the stem.

The seeds are just as potent. One dandelion is capable of giving rise to hundreds of others. That’s why you’ve got to handle them well if you indeed want to get rid of them.

How Does Pre-emergent Herbicide Works

In order to know the best time and procedure of applying pre-emergents to your lawn, let’s take a look at how it works.

#1. Pre-emergent is for ungerminated weeds

Just as the name suggests, pre-emergents are herbicides suited for weeds that are yet to appear on the surface of the soil. It means they are ineffective on existing or germinated weeds. Pre-emergent has growth inhibitors that form a barrier against the further growth of the weeds. Likewise, it prevents the weed from taking further roots into the soil.

#2. Pre-emergents can affect your turf

Turfs are not immune to pre-emergents. A lot of folks have complained about their lawn being dormant after they applied pre-emergents. This side effect is the core reason you shouldn’t seed while applying pre-emergents.

This is because the pre-emergents can treat your turf like a weed. For best results, you can seed your lawn about six weeks before you apply the pre-emergents. Alternatively, you can seed after three months after you’ve applied the pre-emergents.

#3. Pre-emergents acts only in areas it’s applied

You shouldn’t expect your pre-emergents to work 100% if it’s not applied correctly. The goal should be to cover as many surface areas as possible.

Suppose you apply your spray in your entire lawn, leaving a fraction unattended to, you’ll still have dandelions to deal with in the ignored area.

How To Apply Pre-Emergents

After all said, let’s take a look at how to apply the pre-emergents on your lawn.

#1. Clear The Lawn Of Debris

Debris can be strong opposition to the good work you seek to accomplish in your lawn. If the pre-emergent falls on the debris it obviously won’t touch the soil.

And if you remove the debris after applying the PE, the pre-emergent granules may go with. It’s advisable you tend your lawn, raking out all of the unwanted stuff before the main herbicide application begins.

#2. Choose The Type Of Granules

The primary ways pre-emergents can be applied are as granules or liquid formulations. Both of them are pretty effective. The granules are water-soluble and will decompose when it comes in contact with moisture.

The smaller the granule size the better the product will work however.

The water formulations, on the other hand, start to work almost immediately it is applied and because it hits the ground as a mist it gets the best coverage over the soil surface. Liquids will give you the best results but you have to ensure you mix your tank correctly and apply evenly to avoid any under or over application to various parts ofyour lawn.

Liquid products tend to work better but also tend to be better suited to people that have experience spraying products evenly and accurately onto the lawn.

#3. Don’t Apply It On Hard Surfaces

Irrespective of the type of pre-emergent that best suits you, ensure you don’t spray it on hard surfaces where water can easily wash it away unto unwanted areas.

Such surfaces include roads, pavements, or walkways. Just ensure you channel the energy towards the lawn. A lot of folks prefer granules because anyone that falls on the wrong surface can be blow back onto the grass or swept up easily.

#4. Water The Lawn

Pre-emergents are water-activated. The water mixes with the herbicide to form pre-emergent barriers in the top couple inches below the soil surface.

For best results, water the lawn, within 21 days after applying the herbicide. You can do this just a few days before the rainfall, or you can use any artificial watering or irrigation technique to supply water to the lawn.

If you want to you can apply your PE to the lawn days ahead of a rain storm and it won’t active until the rain finally comes down. If you are applying a little late in the season then it’s usually best to run your sprinklers right away to active the product as soon as possible.

When To Apply Pre-Emergent Herbicides

The best time to apply pre-emergents is in early Spring or early-Fall. During these times dandelions are most likely to sprout from seed. That means the herbicide can stop them before they root down. Spring herbicidal application is pretty effective because it will prevent the weeds that often rise in Summer.

See this post for more on killing the existing Dandelions in your lawn as the PE won’t do that at all.

You can apply the pre-emergents when the Spring temperature is still dancing between 36 to 72 degrees Fahrenheit. But an optimum temperature of 50-55 degrees is best. This should be around February/March/April (depending on where you live), about a week or two before the bulk of dandelion seeds begin germinating.

Nonetheless, pre-emergents herbicides can be applied at any time in the year as long as it’s not during overseeding.

Just as I mentioned earlier, if you want to carry out overseeding in your lawn, apply the pre-emergents about three months after your overseeding operation. Another way around it is to seed now and apply the pre-emergents in about six weeks later although you may lose some of your new grass to root die-off at such an early stage of development.

Natural Way Of Removing Dandelion

If you don’t like the idea of using chemicals of any sort on your lawn, then a natural dandelion removal plan should work. Forget the fancy word, “natural,” what I mean is hand-digging the lawn for dandelions.

This is really not a very fun method. It’s pretty stressful and difficult, especially if you’ve got a very large lawn. Nonetheless, it is the most effective way of getting rid of stubborn weeds. With hand-digging, you can remove the plant with its taproots.

Truely the best way to dig them up is to not be gentle. Dig a wide circle around the center of the dandelion and pull up as much ground as you possibly can, weeds, grass, and dirt all together. Once out of the ground it will be easier to tease the main tap root out of the removed soil. Once removed then you can place the soil back in the hole and wait for the grass around the weed to recover.

I’ll emphasize it again. You’ve got to remove the entire taproot of the dandelion if at all possible and certainly the first 6 inches of it to have any chance of it not regrowing. This is because a few inches of the taproot is more enough to give rise to another dandelion in the space where you just removed its parent.

For best results, this should be carried out in spring, just as the first set of dandelion begin to poking their heads out of the ground. The reason for this is because the ground ismost likely to be workable this time of year and the new growth of old dandelions will make it easier to find the worst offenders.

Truth is, you probably won’t be able to pull out all of them in a day or even a week but work at it occasionally all year and you’ll see gradual improvement.

Pre-emergents are very effective on preventing new dandelions. A lot of folks love this weed however for its numerous health benefits, but that shouldn’t mean you have to keep them in your lawn. If you are curious if they are actually bad for the lawn then that’s another topic all together. See my take on it here.