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How to Mix Fertilizer With Grass Seed

grass,lawn image by Greg Pickens from

Rejuvenating a lawn after the winter season often requires reseeding. Mixing a granular fertilizer with the grass seed is an efficient method for lawn propagation. The fertilizer will give the grass seed an extra boost after it has germinated. You might notice enhanced weed growth, too, as the fertilizer could boost undesired growth. Using the proper method for mixing fertilizer with grass seed can give you a lush lawn.

Test the soil conditions by taking soil samples in different locations around the lawn reseeding area. Have the samples tested at an agricultural extension service. Results will be returned in approximately 4 to 6 weeks. The laboratory will give specific fertilization and soil pH recommendations for your lawn.

Apply a specified herbicide to eliminate any weeds from the lawn.

Remove any dead thatch material and other debris from the site by raking the area vigorously with the garden rake. The garden rake tines will also aerate the soil and provide soil contact with the seed. Move the thatch material to a compost pile. The compost at the end of the year can be added back onto the lawn for extra organic material.

Mix 1 to 2 pounds grass seed mixture per 1,000 square feet with the recommended fertilizer from the soil test or use approximately a half-pound of 21-7-14 blend fertilizer per 1,000 square feet of lawn area. Combine the materials into the plastic bucket.

Spread the fertilizer and grass seed mixture across the lawn area with the seed broadcaster.

Irrigate the lawn area with the garden hose and sprinkler. Add approximately 1 to 2 inches of water per week. This amount depends fully on local rainfall.

Mow the new grass when it reaches a height of 3½ inches. Set the mower deck between 2 and 2½ inches high.


Consult the agricultural extension service for grass seed that will thrive in your area. Different areas and climates around the country will require various grass seed mixtures along with sun light or shade requirements.

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