To seed or not to seed, that is the question. Spring is a great time to over seed an existing lawn. Sunshine is abundant in those normally shady spots and springtime rains assure an adequate supply of moisture. Spring is also the only time that crabgrass can be controlled with a pre-emergent. Unfortunately, seeding and crabgrass control don’t mix. Manufacturers recommend waiting four months after a pre-emergent is applied before planting new grass seed.
Step 1: Crabgrass seeds begin to germinate when soil temperatures reach 50 degrees Fahrenheit. Pre-emergent must be applied as soon as grass seeds begin to germinate. As luck would have it, yellow forsythia bushes bloom when the soil temperature reaches 50 degrees. Pre-emergent should be applied before the forsythia bushes are done blooming. If the yellow forsythia blooms are gone and lilac bushes are in full bloom, it is too late to use a pre-emergent for crabgrass control.
Step 2: Pre-emergent is activated through hydration. Once pre-emergent has been applied, water the lawn with a fine soft spray. After its initial wetting, excessive rainfall or continued watering will inhibit the pre-emergent’s ability to restrict weed growth. Avoid applying pre-emergent when excessive rain is in the forecast.
Step 3: Pre-emergent acts as a protective barrier on top of the soil. Raking, scratching or in any way disturbing the ground in the weeks following pre-emergent application will compromise the pre-emergent’s effectiveness.
Step 4: Corn Gluten is an environmentally friendly and affordable way to prevent crabgrass. A by-product of the corn milling process, corn gluten stops seeds from germinating while simultaneously fertilizing existing plants. Corn gluten inhibits seed germination and root production for up to six weeks. Apply 10 – 20 pounds of corn gluten per 1000 sq ft of lawn, water lightly and allow the lawn to dry completely. Infrequent watering coupled with spring and fall application will enhance corn gluten’s ability to insure a chemical free, weed free, thick, luscious lawn.
Step 5: If you can’t decide between over seeding or crabgrass control, try a product with the active ingredient Tupersan/Siduron. It is the only chemical on the market today which can selectively inhibit crabgrass germination while allowing fescues and other cool season grasses to grow. Tupersan/Siduron must be applied during or immediately following seed application. Left undisturbed, Tupersan/Siduron can control crabgrass for up to five weeks.