

Premium fall lawn fertilizer
Late-season lawn fertilizer for greening, deep rooting and resilience to winter injury.
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Your lawn's fall game plan starts here
Fall Fortify Plus is a liquid lawn fertilizer that preps your grass for winter from the roots up. It skips the potassium found in traditional winterizers, so you get less disease pressure when things turn cool and damp. Connect the included hose-end sprayer and you're done in 10 minutes. Pair it with your Custom Lawn Plan for a stronger spring.
What makes Fall Fortify Plus different
- Builds deeper roots for a stronger spring lawn
- Iron deepens green color without a growth flush — better-looking lawn, no extra mowing
- No potassium means less disease pressure
- Hooks up to your hose for easy application
- Works on all common grass types
- Covers up to 5,000 sq ft per pouch
- Made without pesticides or harsh chemicals
Ingredients
Nitrogen: Fuels deep rooting and helps your lawn recover and hold up through winter stress.
Iron: Extends a richer, deeper green color well into fall so your lawn looks good longer.
Manganese and micronutrients: Support steady, healthy grass growth as temperatures cool down.
How to use
Apply between August and October, when temperatures start to cool.
- Water your lawn well the day before, or apply after rain so the soil is hydrated.
- Connect the hose-end sprayer to your garden hose and attach the pouch.
- Turn on the water and apply evenly across your lawn. A full pouch takes about 10 minutes.
- Let your lawn dry completely so the nutrients absorb into the soil. Once dry, it's all yours again.
- Reapply every 4 weeks until mid-October for the best results.
Customer reviews
5.0
Based on 1 reviews
Good stuff
The products are doing as stated,centipede here,grows slow ,but the color is good and grass is spreading
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Questions & answers
6 questions
Question: I just planted new sod. How soon can/should I begin using Fall Fortify? Or is there another fertilizer you recommend for new sod? thanks.
Louisa D.
You sure can use Sunday on the new sod in your lawn! Since sod is well-fertilized when you lay it from the manufacturer, we recommend waiting a few weeks after installation (until roots are established and you can't lift it off the soil) before applying our nutrients. This will help avoid over-fertilization. You can find more information about caring for your new sod lawn here: https://www.getsunday.com/shed/lawn/caring-for-your-new-sod-lawn
Question: Can I use this after aeration and overseeding
Louisa D.
If you plan on aerating your lawn, we recommend aerating first, waiting about 1 week, then resuming your nutrient applications. Sunday nutrients may be applied directly before or after seeding or patching your lawn. For best results, seed first and wait for about 60% of the grass to sprout—usually around three weeks—before applying nutrients. This ensures new seedlings can absorb them effectively. For more on these topics, check out our blog on the website-- The Shed! https://www.getsunday.com/shed/lawn/do-you-need-to-aerate-your-lawn
Question: How long after overseeding and filling in a couple puppy patches with Sunday Pet Lawn Seed would you recommend waiting before applying Fall Fortify product (if at all)? Wondering if I apply this season or hold it until next. Thanks in advance.
Louisa D.
Great question! We recommend waiting for those patches to begin sprouting before applying any nutrients.
Question: I started growing grass seed about three weeks ago and I'm getting ready to mow for the first time. . Can I apply this before or after my first mowing? Will it help the new grass make it through the winter?
Louisa D.
We recommend applying after you mow! If you choose to apply before mowing, we recommend waiting 24 hours after applying before you mow.
Question: It says to “water your lawn thoroughly post-application”, does that mean immediately after applying the fertilizer, before it dries? Or does that mean after you’ve fully followed the instructions, including after allowing the grass to dry?
Louisa D.
Great question! We recommend healthy watering practices at least 24 hours after your Sunday application to give it ample time to dry.

