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How to Calculate Grass Seed for Overseeding

A lush, green lawn begins with proper care practices. Regular mowing, ample watering, and a good fertilizing schedule are all ways to have a successful lawn. One other practice that is equally important is periodic overseeding of the lawn. As grass plants age and mature, a few of them will inevitably die out. Overseeding will allow new grass plants to take hold in these areas and keep your lawn looking thick and lush. However, to overseed successfully you need to calculate the right amount of grass seed for overseeding.

Calculate the square footage of the area you need to overseed. Measure the length and width of the area and multiply them together. So if you measure 50 feet by 30 feet, your square footage is 1,500 square feet.

Refer to the grass seed packaging for the overseeding rate. Most grass seed should be applied at the rate of 2 to 4 lbs. per 1,000 square feet.

Calculate the amount of grass seed you need to apply to the lawn. Take your overseeding rate and divide it by 1,000. Multiply that number by your square footage that you calculated. For example if your overseeding rate is 4 lbs. per 1,000 square feet, you would divide that by 1,000, and then multiply by your square footage (1,500 from step 1 example). This would yield 6 lbs. of grass seed needed to overseed.

Calculate Grass Seed For Overseeding

Healthy, dense turf is prized for its contribution to the overall appearance of a yard or landscape and as a groundcover. Where a lawn is thin or completely brown in winter but is otherwise healthy with no major problems related to diseases, pests, weeds, compaction, drainage, a too-thick thatch layer or soil nutrition, overseeding provides a viable means to improve the appearance of your lawn. Measure the edges of the lawn area you plan to overseed in feet. If the lawn space has more than four approximate edges or has an irregular shape, subdivide the area into smaller squares or rectangles and measure adjacent edges on each rectangle. For example, a rectangle 10 feet wide by 5 feet long would be 50 square feet. Multiply the number of 1,000-foot sections in your lawn -- or the decimal you calculated for a small lawn -- by the seeding rate for the turf species.

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