How Much 10-10-10 Do You Use on One-Month-Old Sod?

New Grass Requirements

• During the first 30 to 45 days after laying new sod, water is the only thing your grass needs. A balanced fertilizer, like 10-10-10 is not needed before that, and if it is added too soon, it may leach out of the sod, concentrating in runoff water, which can be bad for the environment. One way to determine whether balanced fertilizer is needed is to look at the edges of the sodded area. If the sod at the edges has begun to lose some of its bright green color, it is time to apply a balanced fertilizer.

Soil Testing

• The best way to prepare soil for new sod and provide the best growing environment for the first 30 to 45 days is to perform a soil test before installing sod. Test kits, available from garden centers, will provide information on the soil's pH and levels of nutrients and micronutrients. Standard test kits will not reveal nitrogen levels in the soil, but specialized test kits will do so. The test kit results will determine which fertilizers and soil amendments should be added to the area before you lay sod.

Fertilizer Specifics

• A 10-10-10 fertilizer contains 10 percent each of nitrogen and oxidized forms of phosphate and potassium -- known collectively as NPK. All are nutrients essential to plant health. A 10-10-10 fertilizer is generally marketed for vegetables and green plants, but could also be used on sod after the first 30 to 45 days. A 3 pound bag of time-release 10-10-10 covers a 150 square foot area. Fertilizers intended specifically for new turf grass, either grown from seed, plugs or sod, feature different percentages of major nutrients. One major brand features a 24-25-4 ratio. Another product features 7-12-15.

Nitrogen Needs

• A 10-10-10 fertilizer contains a balanced ratio of the three major nutrients, but new sod may need more nitrogen. If major soil nutrients were added in accordance to test kit results before you laid sod, it may be better to add supplemental nitrogen at the end of the first month after laying sod. Apply nitrogen at the rate of 1 pound nitrogen per 1,000 square feet of turf area. Repeat this application again 30 days later. In warm areas where sod may be installed in winter, wait to apply nitrogen until grass has "greened up."