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Premium liquid lawn fertilizer — iron
Supercharged iron citrate and high nitrogen blend for the deepest lawn greening and growth.
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Your lawn's new favorite color
Iron Boost is a 20-0-1 liquid iron fertilizer for lawn powered by chelated iron citrate for fast foliar absorption. It greens up your grass without pushing excessive growth. Potassium and seaweed extract handle the stress so every blade stays strong. Works on all grass types, and the included sprayer means you just connect and go. Pair it with a Custom Lawn Plan for the full picture.
What makes Iron Boost Liquid Fertilizer (2-pack) different
- Greens and feeds in one step with a 20-0-1 formula
- Iron absorbs fast for quicker, deeper greening
- Hose-end sprayer included, no extra gear
- Works on every lawn and grass type
- Potassium and seaweed extract for resilience
- No pesticides, just nutrients your lawn needs
Ingredients
Nitrogen: Feeds healthy grass growth so your lawn fills in thick and stays green.
Iron citrate: A chelated form of iron that absorbs quickly for rapid deep greening, the kind of green your neighbors will notice.
Potassium and seaweed extract: Helps your lawn handle heat, drought, and everyday stress so it stays strong between applications.
How to use
Apply early morning or evening when your lawn is well hydrated. Avoid use on drought-stressed or heat-stressed lawns.
- Connect the universal sprayer to your hose and the fertilizer pouch. The sprayer is designed for the right mix of water and fertilizer.
- Spray evenly across your lawn until the pouch is empty. This should take about 10 to 15 minutes.
- Once the fertilizer dries, you're good to get back on your grass.
- Reapply every 4 to 6 weeks from spring through fall.
- Keep the sprayer for future applications.

Customer reviews
5.0
Based on 2 reviews
You can tell the difference!
I applied Iron boost to my shop lawn but not my house lawn. The shop lawn is considerably a deeper, more lush green than the house lawn.
Sunday
Hi Alison! So wonderful to hear that you can see such a clear difference in the lushness and color of your shop lawn after using Iron Boost. We look forward to helping you achieve the same amazing results for your house lawn too!
Was this review helpful?Amazing !
I am a new Sunday customer. One bag of this Iron Boost was the first Sunday product I applied to my lawn. I can't believe how much darker the established (fescue) grass became in only 12 hours overnight! I can't wait to apply the weed killer, now that the Iron Boost has made it much easier to see all the weeds. Thank You so much.
Was this review helpful?
Questions & answers
8 questions
Question: How much of the pouch do I use? My lawn is 1,000 sq ft. The pouch says it's good for 5,000 sq ft; the answer to a question below (4/26/24) says that a pouch is good for 2,500 sq ft; and the instructions above say to use the entire pouch. Not sure if I should use about 20%, about half, or the whole thing. Thanks!
Jeff McConathy
Great question! Each pouch covers roughly 2,500 square feet. Because this is a 2-pack, the entire order covers 5,000 square feet. If you're applying to a 1,000 square foot yard, we recommend using half of one pouch at a time. Always wait at least 7 days between fertilizer applications.
Question: How long after I use the Iron Boost can I put down new seed?
Jeff McConathy
Great question! You can seed as soon as the fertilizer dries.
Question: After using Iron Boost, how long should I wait before watering my lawn again?
Louisa D.
We recommend waiting 24 hours after application before watering!
Question: Am I supposed to go through one full pouch each time I apply? I used this pouch on my entire lawn, front and back, and only used a portion of the pouch.
Louisa D.
Each pouch should cover 2,500 square feet when applied evenly. One pouch should take approximately 10-15 minutes to empty when using our hose-end sprayer. If you are having trouble with your application, our team would love to help you! You can reach them at [email protected] or by calling 415-903-6932.
Question: Will this kill newly planted trees?
Louisa D.
Our nutrients do not contain any herbicide so it will not actively kill anything; however, it is formulated specifically for turfgrass so we don't recommend applying directly to other plants for best results.
