A lot of people ask whether it’s better to fertilize a lawn before or after it rains. It’s a fair question. After all, it costs money, and no one wants to see fertilizer washing away down the storm drains. But mild rain isn’t always a bad thing. In some cases, it can actually help fertilizer applications work better. It really comes down to fertilizer timing and what kind you’re using—granular or liquid.
Rain Can Help—or Hurt—Granular Fertilizer
Granular fertilizer comes in small, solid pellets. These need moisture to break down and move into the soil. That’s why a little rain can actually be helpful if you’re using this type of product on a dry lawn.
“It can be beneficial to apply granular fertilizers right before a light rain but be sure to avoid application before a heavy downpour,” shares Matthew Koch, Ph.D., Director of Biotechnology and Genetics at The Scotts Miracle-Gro Company. “Moisture helps dissolve the granules and move the valuable nutrients into the soil where the grass roots can absorb them efficiently.”
But the key is light rain. When the weather forecast calls for a big storm, it’s better to wait. “If heavy rainfall is expected, this can wash the fertilizer away before it has a chance to soak in,” Koch explains. That means wasted product and missed results.
If you’re unsure about the forecast or don’t want to rely on the weather, you can always water the lawn yourself after applying. “A simple watering of the lawn lightly after applying a granular fertilizer is also effective and reduces the risk of waste and runoff,” notes Koch.
One granular option he recommends is O.M. Scotts & Sons Natural Grass Food, which is made with premium nutrient sources and is safe to use around kids and pets. “It strengthens grass from the roots up,” he adds.
Here are a few times when it’s smart to apply granular fertilizer:
- When light, steady rainy weather is in the forecast
- When you can water the lawn lightly afterward
- When you have dry soil and grass is growing
- During cooler parts of the day, like early morning or evening
Liquid Fertilizer Should Wait Until After the Rain
Liquid fertilizers are different. Instead of soaking into the soil slowly, they work through the grass blades and top layer of the soil. That means they need to stick around a bit—and applying liquid fertilizer before rain can interfere with that.
“Ideally, liquid fertilizers should be applied to a damp, not saturated, lawn, ensuring no rain is expected for several hours after application,” explains Koch. “Applying liquid fertilizer just before rain can cause it to wash off the blades and soil surface before it can be absorbed, reducing its effectiveness.”
So, what’s the best move? Wait until after it rains. The period of time when your lawn dries slightly—but isn’t completely dry—that’s your window. “After a rainfall or watering — once the lawn has had time to dry slightly — is the perfect time to apply a liquid product like Scotts® Liquid Turf Builder® with Plus 2 Weed Control,” notes Koch. “This option feeds your grass while tackling common broadleaf weeds; just make sure to check the forecast and allow at least 48 hours without rain after applying so the product can work properly.”
Some products even allow you to fertilize and water at the same time. “Scotts® Liquid Turf Builder® Lawn Food is also a great 2-in-1 liquid fertilizer option that lets you feed and water your grass at the same time,” he highlights. “Simply attach the product to your gardening hose and spray evenly over your lawn. If your lawn needs watering beforehand, make sure to water thoroughly or allow for rainfall 24 hours before application.”
Timing Is Everything
So when should you fertilize—before or after rain? The answer depends on what you're using. “In short, if you're using a granular fertilizer, water manually after application or apply it before a light rain,” recommends Koch. “If you're using a liquid fertilizer, apply it after rain once the lawn has had time to dry slightly.”
That’s the takeaway. Use light rain to your advantage with granular fertilizer pellets, and avoid rain altogether with liquid products.
Here's a quick comparison for clarity:
Granular Fertilizer
- Apply before light rainfall
- Avoid applying before heavy rain
- Water lightly afterward if needed
- Works best when soil is dry but not compacted
Liquid Fertilizer
- Wait until after rain
- Apply when grass is damp, not soaked
- Make sure no rain is expected for at least 24–48 hours
- Can also be applied using hose-end sprayers
By picking the right type of lawn care products and watching the weather, you’ll get better results and waste less.
FAQ
What if I accidentally fertilized before a heavy rain?
If you used granular fertilizer and it rained heavily soon after, some of the product may have been washed away. You might need to reapply, but it’s best to wait a few days, observe how your lawn responds, and follow the product label for safe application of additional fertilizer. If it was liquid fertilizer, the essential nutrients likely didn’t have time to be absorbed. In that case, you’ll likely need to reapply once the lawn has dried out again.
Is morning or evening better for fertilization around rain?
Either can work, depending on the weather. In general, early morning is a good choice, especially if you’re applying before light rain or watering afterward. Avoid the hottest part of the day, and don’t apply during wind, which can cause uneven spread or drift.
