Best time to fertilize lawn in different hardiness zones

Fertilizers are a fundamental component of the growth of a healthy lawn. Choosing the best time to fertilize lawn is essential. Applying essential nutrients to your grass becomes more crucial when you’re living in an environment that holds short growth spells and keep changing day/night temperatures frequently. The majority of lawn keepers don’t consider fertilizing their lawns for they don’t know when and how to fertilize them amid changing seasons or have limited knowledge about the requirement of nutrients level at different growth stages of grass, they’re growing. The right fertilizer and right time always give splendid growth and vigor to your lawn and increase its ability to surpass dormancy successfully.

best time to fertilize lawn

Usually, the spring is the best period to fertilize a lawn after it starts regrowth and the surface temperatures reach between 80-95°F in warm-season grasses. The best time to fertilize lawn is suggested in the afternoon since some fertilizers may burn the grass foliage during high temperatures if the granules or concentrated water droplets stay on their surface. Often, granular fertilizers need immediate watering after they are applied, for they need moisture to dissolve nutrients so that they become a part of your lawn. Most parts of the country observe spring in the mid of April. High nitrogenous fertilizers with a low percentage of Phosphorus and Potassium are required in the spring to boost both germination and growth at the moment. A fertilizer label always mentions the ratios of nutrients in N: P: K sequence where N stands for Nitrogen, P for Phosphorus, and K for Potassium. The best ratio for spring application is 4:1:2 which, means 4 parts nitrogen, 1-part phosphorus, and 2 parts potassium. 3-4 pounds of the said ratio will be sufficient for 1000 square feet of lawn in split doses throughout the growing season. Generally, the application of granules is simple and gives you ease to broadcast it after watering your lawn that stops evaporation, dissolves faster, and reaches the root zone more quickly. Often, such fertilization reflects its response to growth and color of grass on 3rd day after application.

Fertilizers are a fundamental component of the growth of a healthy lawn. Choosing the best time to fertilizer lawn is essential. Applying essential nutrients to your grass becomes more crucial

If the first application was a chemical fertilizer, then you may repeat it after one month. Otherwise, delay it 6-8 weeks in case of organic or a slow-release fertilizer.

For fall fertilization, focus on higher percentages of Phosphorus and Potassium and low nitrogen fertilizers as the roots remain alive in fall to develop an extensive root system during dormancy that provides better growth in next spring.

On the other hand, cool-season lawns need heavy fertilizing in the fall and light in early spring when the temperatures range between 60 to 70°F. Since their dormancy starts during peak summer temperatures, it is advisable to fertilize cool-season grasses before going into dormancy. Usually, two pounds of 4:1:2 ratios (20:5:10) fertilizers are sufficient to meet the nutrient requirements of 1000 square feet of lawn annually.

Best time to fertilize lawn grass (warm season)

Common warm-season grasses in the US include Bermuda, St. Augustine, and Zoysia grasses. These grasses are adaptable to the lawns in USDA Hardiness zones 5 through 10. Whereas further categorization fits Zoysia spp in the hardiness zones 5 to 10, Bermuda or Cynodon spp best adaptable to zones 7 through 10, and St. Augustine to USDA hardiness zones 8 to 10, need fertilization starting from the mid to end of April, June, September, and late October. Every fertilizer application is grass condition dependent and needs to be given during the active growth period. The color of grass may be used as a strong base to determine the growth. Lush-green color is a clear indication that the lawn is growing at its full potential and could utilize the fertilizer dose fully to increase its biomass. If the color of the grass starts fading, it means the time of proper fertilizing is over.

Best time to fertilize lawn grass (cool season)

Cool-season grasses observe active growth during spring and fall and start fading with an increase in surface temperatures reaching beyond 90°F. Cool-season grasses’ active growth continues in the temperature ranges between 40 to 90 °F.  The grasses like Bentgrass, Kentucky bluegrass, Rough bluegrass, Tall fescue, Annual ryegrass, Fine Fescue, and Perennial ryegrass fall in the category of cool-season grasses, and they are adaptable to USDA harness zones 7-10. The best time to fertilize them is soon after coming out of dormancy in September, followed by 2nd application in October. The third application suggested in March and 4th application just before going into dormancy. These grasses often stop growth below 40 °F so, be vigilant on limiting the fertilization practices around this temperature range.

Here are some frequently asked questions about the best time to fertilize lawn:

What is the best time of day to fertilize lawn?

Our advice is not to do it in the morning. The best time to fertilize your lawn is in the late hours of the day. Either in the afternoon or in the early evening. Don’t forget to use an appropriate spreader and don’t forget that sometimes less is better.

Should I water lawn after fertilizing?

Yes, you should. It’s very important to push the fertilizer from the grass itself to the soil and roots.
You can also let the rain do the work for you. Just make sure you check the forecast and fertilize before a rainfall.

What if it rains after I fertilize my lawn?

Don’t panic ! It’s actually the best time to fertilize lawn before it rains, if the rain is going to be light. It will help wash the fertilizer from the grass and put it where it was intended to go – into the soil and roots..

Is it OK to fertilize when hot?

Not really. You should fertilize in early spring, if you do it in the hot summer there’s a big chance to ruin your lawn. Concentrate on basic maintenance in the hot months. In this case, less is better.

How long do you wait to water after fertilizing?

You don’t have to wait. Check the forecast and fertilize before it rains and let the rain water instead of you. If not, just do it right after you apply fertilizer, or in the next 24 hours after.

Should I fertilize before or after mowing?

The short answer is before mowing. It’s better to apply fertilizer on a mowed lawn, simply because it will reach closer to the soil, where it needs to be active. Give it a few days so it can absorb. Don’t fertilize in the hot months.

How long do you have to stay off lawn after fertilizing?

You shouldn’t let your kids or pets back on the lawn right after yo apply your fertilizer. We recommend waiting 2 to 3 days, making sure you water your lawn in that time so the fertilizer can get absorbed. Once that happens it’s safe for you, your family and pets to go back on the lawn.

How long after fertilizing lawn is it safe for pets?

It should be safe for your pets to be back on the grass after 2 to 3 days. In that time, you should have watered and no granules should be visible on the grass itself. Once the fertilizer is where it should be – in the soil, it should be safe to let out your pets.

Can you fertilize your lawn too early?

Yes, you can. You shouldn’t apply fertilizer in the winter, as that’s not the best time to fertilize lawn. You should wait for spring. When you notice that the grass is starting to grow faster, it’s time to start preparing for fertilizer application. Make sure you time it right – check the forecast and make sure your pets and kids will not run wild just after you spread it.

Can you fertilize your lawn when you have a well?

If your well is capped, it should not be a problem. If your lawn is close to running water, you should be careful. Fertilizers work as well on algae and similar unwanted vegetation as on grass. So if the fertilizer gets in the water, and it’s possible that it does, you might have an unpleasant surprise.

Can you put fertilizer on dry grass?

Yes, you can, and you probably should. If the grass died because of the weather being too hot, you will have to wait for the weather to cool down a bit before you notice any results. Make sure you water 24-48 hours after applying fertilizer to dry grass.