What is crabgrass?
Crabgrass is an annual summer plant, germinating from seed every spring and will grow more prominent as the weather gets warmer. Crabgrass produces seed in late summer and is neutralized by a hard frost in fall. The crabgrass seed that germinates in your lawn this spring originated late last summer. If you had crabgrass in your yard last year, it is essential that you take steps to control it this year.

Controlling crabgrass at the seed stage.
The most efficient way to control crabgrass is to stop the crabgrass seed from becoming settled in your lawn by applying a preemergent herbicide, usually referred to as crabgrass preventer. A pre-emergent herbicide forms a herbicide barrier at the surface of the soil. As a crabgrass seed germinates, the emerging root contacts the herbicide barrier. The preemergent herbicide breaks up healthy root growth and the crabgrass seedling soon wither without ever being noticed.

For most preemergent herbicides work properly, the application must be performed before crabgrass seed germinating. The preemergent herbicide needs to be in the soil as the crabgrass seed grows so the new root will contact the herbicide.

Crabgrass seed begins sprouting when the temperature of the at a two-inch depth reaches 50° to 55° F for at least 2-3 consecutive days. Exactly when crabgrass seed germination occurs depends on geographic location – areas in Northeastern Pennsylvania germination will happen in late spring. Specific crabgrass control formulations also provide post-emergent control of crabgrass. They control crabgrass seed as it germinates like other preemergent herbicides as well as control small crabgrass plants that have sprouted and had a leaf or two present at the time it is applied (typically up to four weeks after germination).

The advantage of using a spring fertilizer with crabgrass preventer formulation is that you have much greater flexibility on when you can apply the product. If you miss the date of crabgrass seed germination by up to four weeks, it will still control the tiny crabgrass plants that have already started to grow as well as any crabgrass seed that has yet to germinate.

The fertilizer component will assist in greening up the lawn, growing and most importantly, will stimulate the existing turfgrass plants to fill in thin areas creating a thicker, denser stand of turf. The increased turf density will help the turfgrass plants crowd out crabgrass.

Spring fertilizer with crabgrass preventer is applied to a dry lawn, but it is crucial that not long after application of the preemergent herbicide and fertilizer combination product the lawn is watered or rain occurs. The preemergent herbicide must be moved off the leaves and down to the soil surface where it is useful. Watering right after application is the best time. The sooner you can water after the product has been applied the better, and the product should be watered in within 24 hours after application at the latest.

Keep in mind; timing is everything for this lawn weed problem – for the best crabgrass control and a healthier lawn this year consider contacting Green Machine Lawn Care to perform spring fertilization and crabgrass control.