Lawn Care Forum banner

MQ's Liquid Lawn Fertilizing Plan

75071 Views 349 Replies 85 Participants Last post by  SouthernTiftuf
I have gotten a few questions about how and what I was going to do this year with spraying ALL my fertilizer apps this year so I figured I would post it here so if anyone else has any questions or suggestions they can put them here.

A little back story, towards the end of last year I was really wanting to do this as I already have a good Sprayer and I already apply stuff at least twice a month. My current stash of fertilizer was getting low and I knew I was going to be needing to stock up again for the coming year. The current fertilizer I was using was a Lebanon NX-PRO Fairway grade fertilizer and was a pretty good fertilizer as it was 22-0-16 and had a very small prill size of SGN 145 and also contained Iron and some Micros and was about 60% slow release. The great thing about this Lebanon fertilizer was that the prill was homogenous, which basically means that the slow release component is the same no matter if you cut or break up the prill, so the slow release isn't effected. But even at that small of a prill size, it still sat on top of my turf for a good week or two before it moved down into the soil, which for me was not good as I use my groomer and catch all my clippings so this really pushed me even more towards the liquid side.

Late last year I started doing some research on the whole topic to see what was actually feasible to do and whether it would be cost effective to actually spray instead of using a granular fertilizer. With my initial searching I was going to use already mixed liquid fertilizer that had a slow release component but that was not economically feasible as the prices were very expensive plus having to pay shipping on top of that, I even inquired at Site One and even though it was a little cheaper it still wasn't viable to go that route.

Enter cheap Urea(46-0-0) and Ammonium Sulfate(21-0-0), these two heavy hitters are both water soluble and provide a big bang for the buck as they can easily be melted down in tap water and sprayed easily, I will get back to these two in a moment. I did a little more research and found that these two can be sprayed fairly easily but require more carrier(water) to be safely applied. Everything I read said to apply with AT LEAST 2-3 gallons of water/K and not to apply more than 1 lb on Nitrogen/K per application as the salts in the fertilizer can dry out the leaf blade and cause temporary browning of the lawn. I also found that after 4 hours of the fertilizer sitting on the leaf it will absorb basically all it can in those 4 hours and then can be rinsed off and into the soil.

I also stumbled across Nitrogen Stabilizers, which can be added to the mix to help the Urea from volatilization, denitrification and leaching. It basically allows the nitrogen to stay in the soil longer and give a "slow release" effect. This is also the same basic ingredient in UFLEXX and UMAXX fertilizers, if you have heard of them before. I will say that this stuff isn't cheap as you can only buy it in 25 lb buckets but you only need .20-.40 oz. per pound of fertilizer so this bucket will last me 10-15 years :D

I also needed to add Potassium but I DO NOT need Phosphorus as my recent soil test states that I have plenty in my soil. So I wasn't able to find any Potassium Sulfate (0-0-53*) locally (but I didn't look too hard) but I was able to find it here at Greenway Biotech. It was a little more than what I wanted to pay but I needed it and will buy me some time to hunt some down locally or with in an hour or two drive. I did just recently find it at [IMG=]Pestrong[/IMG] for a little cheaper and I may go this route if I can't source it locally but I would like to get it local to keep the costs down.

The last component to my fertilizer is going to be Iron. I did some extensive research on this too as I wanted to get away from FAS(Ferrous Ammonium Sulfate) and was looking for some chelated iron that would give a more lasting effect in the lawn. I finally decided on DPTA Iron as this looks to be the most suitable chelated iron for my pH level. I may do another write up later about all different types of chelated iron there is and what is suitable for what. DPTA iron will stay stable in soil pH up to 7.0. These types of iron are a lot more expensive than Ferrous Sulfate but will also be more available to the grass for a longer period of time. This is more of a luxury additive and could be omitted if it becomes too cost prohibitive.

Let me wrap this up for now and go over my plan and costs so everyone has a good idea of what's going on. I was going to wait until I actually started using all of this but why not get the info out there and let the great minds we have here go over this.

My plan going forward is to apply 1lb of Urea, AS and PS with 2-4 oz of Iron/1,000 sq/ft(67-0-53) which will give me a little over half a pound of Nitrogen and a half pound of Potassium and I will be adding this when I spray my PGR so every 3 weeks or so I will be applying this to the lawn. I will also be adding the Nitrogen Stabilizer to help lengthen the effects of the Nitrogen. This is all just my base plan and is subject to change depending on the outcomes of my spraying. The one great thing about this plan is I can basically add or subtract anything I want at anytime I want to adjust it to current growing conditions. I also plan to spray in the evenings and water it in the following morning to get at least 4 hours on the leaf surface and to reduce any chance of burning the turf.


Urea $15 for 50 lbs @ SiteOne
Ammonium Sulfate $22.55 for 50 lbs @ SiteOne
Potassium Sulfate $45 for 25 lbs @
DPTA Iron $50 for 5 lbs @
U-Plus Nitrogen Stabilizer $193* for 25 lbs @ SiteOne

* When I inquired about this product there, they had never heard of it and didn't know exactly what it was and I didn't know exactly how much a bucket of it was going for. After they punched in the item number and brought it up, the guy was like "Is this stuff made of gold!!!" :lol: He said it goes for $300 but said to hang on and did some things on the computer and came back with the price quoted above which was WAY better. I think he gave me the contractors pricing on it which was greatly appreciated :thumbup:

I have enough Nitrogen to last me a good 2-3 years, the only thing I will need to buy more of is the Potassium Sulfate and Iron so my fertilizer budget is greatly reduced and if I can find the Potassium Sulfate locally it will even bring my cost of application down even more.

Cost per application over 8K of lawn

Ammonium Sulfate=$3.61
Potassium Sulfate=$14.40


This is the first time I have actually added everything up and it seems a little high but it's still way cheaper than going with pre packaged liquids and If I can source my Potassium Sulfate locally it will dramatically cut down on the costs and as you can see also is that even with the initial high cost of the U-Plus, it's price per application is relatively low. I understand that what I am doing is not for everyone but I am always willing to try something new that may give me an edge and take it to the next level.

I'm sure I left something out or forgot to mention something but If I remember I will just add it to the thread :thumbup:
See less See more
  • Like
Reactions: 1
1 - 1 of 350 Posts
Love the plan. Iron delivery is so complex but so critical to get your grass to really pop. It drives up the cost quick. I've been very satisfied with the results from this product
Grow More 7450 8-Ounce Organic Iron Chelate Concentrate
Which is on sale for $5 so I bought several just now :D

Probably not as cost effective as a home brew mix but the results were really satisfactory for me. I never used as much water as the label calls for when spraying, just watered it in in a similar fashion as you outlined.
1 - 1 of 350 Posts