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What is Crabgrass

Crabgrass is a weed that most homeowners are well aware of, and a weed we all universally despise. It is an annual grassy weed which proliferates very quickly once it becomes established in a lawn, so it is always best practice to try and remove it as quickly as possible after it is first noticed.

Controlling Crabgrass

Crabgrass, like many other weeds in the lawn, can be effectively controlled over the long term with good management practices and lawn care routines which should be the foundation of all our lawn care.

Regular lawn mowing is important as it removes the majority of the seed heads the weed produces. This is important when we consider that Crabgrass can send out thousands of seeds throughout the entire Summer. Mowing regularly simply removes all these seeds as they are being produced.

Mowing at the correct height for the lawn type is also vitally important as this will allow the lawn to flourish and stay in peak health which can then out-compete many weed infestations. When choosing a lawn mowing height it is always better to mow at a higher height for your lawn type.

Pre-emergent Herbicides For Crabgrass

Crabgrass can be controlled most easily with a pre-emergent herbicide which is applied before the Crabgrass has germinated. The pre-emergent herbicide will have little or no effect once the leaves of the new weeds begin to emerge.

You will need to take note of the exact germination times for your region, as the germination of Crabgrass will vary depending on the exact location and weather of where you live. If you are still unsure about when this may be, simply check with the knowledgeable staff of your local garden store, or consider having a professional come to your property to apply the herbicide, but this will need to be arranged at the end of Winter to get a booking for early Spring.

Pre-emergent herbicides should be watered in lightly so it reaches down past the thatch layer and onto the soil surface, usually a 1/2 inch of watering is sufficient.

Some important aspects to remember when using these herbicides is not to apply it to newly laid sod or seed until the lawn is fully established, and never to seed a new lawn for around 3 months after the use of these herbicides.

Killing Crabgrass With Post Emergent Herbicides

If the window of opportunity to kill Crabgrass with a pre-emergent herbicide was missed, this grassy weed can still be controlled and killed with a post-emergent herbicide. These herbicides may have to be applied several times over the season as each new generation of weeds germinates.

There are several different types of herbicide available, all with different active ingredients, and some are more effective than others. But if we always try to kill Crabgrass when the weed is still young and immature, most of these herbicides will kill crabgrass and other grassy weeds very easily.

Crabgrass and other weedy grasses become far more difficult to kill once these weeds become more mature and established. Once this happens, the homeowner may have to look at some of the more expensive herbicide options to effectively control the infestation.