A Guide to Fertilizing a New Lawn

Fertilizing a new lawn is an important process that helps establish healthy grass. Proper fertilization provides the nutrients lawns need for root development, shoot growth, and overall vigor. Follow this guide to fertilize a new lawn successfully.

Timing Matters

Fertilizing at the right times is key for optimal lawn health.

  • Fertilize newly seeded lawns about 6 weeks after germination when the grass reaches 3 inches tall. Use a starter fertilizer that is higher in phosphorus to promote root and shoot growth.
  • For sod, apply a starter fertilizer as soon as possible after laying it. The roots will absorb nutrients right away.
  • Fertilize in the growing season from early spring through fall based on your grass type. Cool-season grasses like fescue grow best in spring and fall. Warm-season grasses like bermuda thrive in summer.
  • Avoid fertilizing in mid-summer heat or winter dormancy. The grass cannot properly utilize the nutrients.

Select the Right Fertilizer

Choosing a fertilizer specifically formulated for establishing lawns is important.

  • Look for a fertilizer high in phosphorus, the middle number of the NPK ratio. Phosphorus energizes root and shoot growth.
  • Slow-release nitrogen provides a steady feeding over 6-8 weeks. Avoid quick-release nitrogen that can burn tender new grass.
  • Natural or synthetic fertilizers can both be effective. Follow application rates carefully.
  • Fertilizers with added iron provide deep green color. Chelated iron is best for mineral deficiency.
  • Fertilizer spikes, liquids or spreadable granules all work. Pick what is easiest for your lawn size and shape.

Proper Application

Applying fertilizer properly ensures the grass gets the right amount.

  • Read the label and follow instructions for application rate and method. More is not better.
  • Apply half the recommended rate in one direction across the lawn. Apply the other half perpendicular to the first.
  • Spread fertilizer evenly and avoid overlapping areas. Use a spreader for optimal coverage.
  • Water lightly after application to help work the fertilizer into the soil. Avoid runoff into drains or waterways.
  • Consider a soil test every 2-3 years. This helps determine exactly which nutrients the lawn needs.

Ongoing Care

Consistent fertilization and lawn care keeps grass looking its best.

  • Fertilize 2-4 times per year based on your grass type and region. Lawns need regular nutrients.
  • Alternate fertilizer with treatments like aeration, dethatching and overseeding. This reduces soil compaction and improves thickness.
  • Monitor the lawn and look for signs of deficiency like yellowing. Spot treat problem areas if needed.
  • Let grass clippings decompose back into the lawn. They provide free fertilizer full of nitrogen.
  • Adjust fertilizer plans annually as the lawn matures or changes occur. The needs of established turf differ from new grass.

Proper fertilization when starting a new lawn gives it the boost it needs to develop into lush, healthy grass. Follow these tips to determine the right fertilizers and techniques for your specific lawn. With consistent care, your new lawn will establish deep roots and thrive.

Frequently Asked Questions About Fertilizing a New Lawn

What type of fertilizer is best for a new lawn?

Look for fertilizers specifically formulated for new lawns, called starter fertilizers. They have higher levels of phosphorus to stimulate root and shoot growth. Slow-release nitrogen is ideal to feed grass steadily without burning tender new shoots.

When should I fertilize a newly seeded lawn?

Wait until the new grass is about 3 inches tall and has been growing for 6 weeks. This gives the roots time to establish before feeding with fertilizer. Apply a starter fertilizer to promote growth.

How often should I fertilize a new lawn?

Fertilize a new lawn 2-4 times in the first growing season. Space applications 6-8 weeks apart during active growth. Avoid fertilizing in hot summer or winter dormancy. Established lawns only need 2-3 applications per year.

Can I use leftover fertilizer on a new lawn?

It’s best to use a fresh starter fertilizer formulated specifically for new grass. Leftover existing lawn fertilizer may be too high in nitrogen or lack the phosphorus new lawns need. Read labels carefully before applying.

What happens if you don’t fertilize a new lawn?

Lawns may struggle to establish without proper fertilization. Grass may be thin, weak, discolored or grow slowly. Weeds can invade easily without thick turf to choke them out. Proper fertilizer strengthens lawns against stresses like heat, drought and foot traffic.

How soon after laying sod can I fertilize?

Fertilize sod as soon as possible after installation, even the same day. The grass in sod continues living after being laid, so the roots can immediately absorb nutrients from a starter fertilizer to minimize transplant shock.

Should I fertilize before or after aerating a lawn?

It’s best to aerate first then fertilize shortly after. Aerating opens up the soil so fertilizer can more easily reach grass roots. But don’t wait too long after aerating to fertilize. The open soil pores close over time.


Fertilizing correctly provides vital nutrients that lead to lush, thick grass in a new lawn. Use the right products at the proper times with care to avoid over-application. Test soil if possible to understand specific needs. With regular fertilization and proper follow-up care, a new lawn will establish a deep root system and grow into a healthy, beautiful turf.