Choosing the Best Fall Fertilizer for a Lush and Healthy Lawn

To prepare your lawn in Pennsylvania, New Jersey, and Delaware for winter, use a fall fertilizer rich in nitrogen and potassium — and avoid phosphorus unless your soil test specifically calls for it. This strengthens roots, boosts nutrient storage, and ensures your grass greens up faster in spring.

As fall arrives, many homeowners wonder how to keep their lawns healthy through the colder months. The secret lies in applying the right fertilizer — one that strengthens your grass from the roots up.

Here’s what you need to know to give your lawn a strong start before winter hits.

Why Nitrogen and Potassium Matter

Fall is the ideal time to feed your lawn nutrients that promote deep root growth and long-term resilience.

• Nitrogen fuels leaf growth and helps grass store energy for spring green-up.

• Potassium enhances root strength and improves disease resistance, helping your turf withstand freezing temperatures and stress.

Together, these nutrients prepare your lawn to bounce back stronger when warmer weather returns.

Phosphorus Restrictions in the Northeast

Homeowners in Pennsylvania, New Jersey, and Delaware should be aware of local phosphorus restrictions. Many states limit or ban phosphorus in lawn fertilizers to protect waterways from runoff and algae blooms.

If your soil isn’t deficient in phosphorus, choose a phosphorus-free fertilizer (you’ll see a zero in the middle number on the bag, such as 24-0-10).

This ensures compliance with state regulations and supports environmental health.

How to Choose and Apply Fall Fertilizer

Look for a slow-release fertilizer that emphasizes nitrogen and potassium. This provides steady nutrition over several weeks and reduces the risk of nutrient loss.

• Apply in mid to late fall (typically October to early November).

• Water your lawn lightly afterward to help nutrients absorb into the soil.

• Avoid fertilizing before heavy rain to prevent runoff.

Following these steps helps your grass develop stronger roots and store the energy needed for early spring growth.

The Bottom Line

Using the right fertilizer in fall is one of the smartest steps you can take for a greener, thicker lawn in spring. Prioritize nitrogen and potassium, skip the phosphorus unless your soil test calls for it, and apply during the fall growth window.

Your lawn will thank you come April — with vibrant color, improved density, and lasting health throughout the season.