N-Ext RGS Root Growth Stimulant Bottle

[N-Ext] RGS™ Alternative | Root Growth Stimulant Substitute

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Written By: Mark Marino

a Massachusetts Core Applicator License holder and owner/operator of Lawn Phix,

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N Ext RGS Root Growth Stimulant Bottle

Looking for an alternative or substitute for [N-Ext] RGS™ ? Maybe you’re interested in substituting liquids by mixing your own solutions? Even more, looking to save a lot of money?

If you have access to water, then mixing your own RGS concentrate solution is very simple.

The RGS alternative solution is simple: just mix one pound of Kelp4less Extreme Blend in one gallon of water (128 oz.) and you have yourself a nearly identical alternative concentrate. That’s it! And if you follow the [N-Ext] RGS™ label, it’s then 3 oz. of concentrate per gallon of water for every 1,000 sq. ft. (maximum of 6 oz. per 1,000 sq. ft.).

Alternatively you can mix about 14 grams (1/2 oz.) of Extreme Blend per gallon for every 1,000 sq. ft. of turf and have the same solution. So if you don’t want to mix a concentrate, use this formula every time you use humic acid on your grass.

RGS is 6% humic acid, 3% fulvic acid and 3% sea kelp. This means that, since one gallon of RGS weighs 8.7 lbs. (139 ounces by weight), there is approximately 8 oz. of humic acid, and roughly 4 oz. each fulvic acid and sea kelp in each gallon. Breaking down the math even further, you’re applying about 6 grams of humic acid and 3 grams each fulvic acid and sea kelp per 1,000 sq. ft.

Extreme Blend is water soluble powder packed with L-Amino Acids, Humic Acid, Fulvic Acid, and Sea Kelp. Both Kelp4less and N-Ext RGS source their kelp from the Ascophyllum nodosum. So you’re getting the same benefits of RGS but with the addition of essential amino acids – all of these organic acids all-in-one. These ingredients help with plant and root development, photosynthesis, and overall health of your turf.

Kelp4less Extreme Blend16 oz. 128 oz.42,600 sq. ft.

Five pounds of Kelp4less Extreme Blend (with lawnphix coupon code applied at checkout of 15% off) is about $107 (including free shipping). This will cover over 106,000 sq. ft. of turf. That’s roughly $0.70 per 1,000 sq. ft. Cheap!

Compare that to the $123 price tag for five gallons of [N-Ext] RGS™ ?, and that’s $ per 1,000 sq. ft.

N-Ext RGS Liquid$123
Kelp4Less Organic Humic Acid$107*
*with coupon ‘lawnphix’ for 15% off

You’ll save $16 for 5 gallons by mixing it yourself – or $6 if you buy 1 lbs. of Extreme Blend (vs. 1 gallon of RGS). BUT, if you subscribe to their email alerts, you can take advantage of their Two-for-One Tuesdays, where they showcase a product at a 2-for-1 deal. They’ve had an Extreme Blend sale a few times already this year (through March 2021) so you can get two 5 lbs. bags (10 lbs in total) for the same price.

Here’s a few items that may make mixing easier if you choose to mix more than one gallon at a time:

Kelp4Less Extreme Blend

These solutions will last several weeks in a cool area, in a clean and airtight container, such as these jugs on Amazon. I used hot tap water, shake vigorously in one of these containers, and store overnight before using. If you make larger concentrates ahead of time, be sure to shake and agitage prior to use as some sediment may settle to the bottom.

Everyone’s water is different. Depending on your pH, iron content, and other minerals can affect how well these products dissolve. If you use a tow behind sprayer for example, you may need to strain this product in the event that not all humic acid dissolves, as this may clog your sprayer. The best strainers are these 100 micron mesh filters that fit on a 5 gallon bucket.

I’ve never once had an issue with any Kelp4less product in my My4Sons backpack sprayer. I pour the Kelp4less mix right through my basket strainer. It also has a filter at the bottom of the reservoir that catches any smaller granules that might find its way into the tank. So I’m confident, when mixed and strained correctly, will have no problems in any backpack sprayer.

So start saving money today by shopping Kelp4less as your N-Ext Humic12 alternative!

What is N-Ext RGS™?

RGS stands for “Root Growth Stimulant”. It is a liquid lawn care product made by the Greene County Fertilizer Co. containing 6% humic acid, 3% fulvic acid, and 3%.

What is the application rates for RGS?

According to the label, the recommended application rate of RGS is 3 oz per 1,000 sq. ft. and applied monthly. A maximum of 6 oz. per 1,000 sq. ft. The mixture should be at least a 7:1 ratio of water to RSG.

What is Kelp4Less Extreme Blend?

Extreme Blend is an all-in-one solution for lawn care, indoor/outdoor gardeners, growers and more. This popular powder contains all essential L-amino acids, humic acid, fulvic acid, and sea kelp.

What’s the difference between RGS and Extreme Blend?

Both N-Ext RGS & Kelp4less Extreme Blend contain humic acid, fulic acid, and sea kelp (both derived from Ascophyllum nodosum). The main difference is RGS is a pre-mixed liquid concentrate – Extreme Blend is a dry water soluble powder and contains all essential L-amino acids.

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Author's Note: this piece has been updated for accuracy since its first publication on
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Author: Mark Marino
My name is Mark Marino, and I am the founder, owner, and operator of Lawn Phix. With a passion for lawn care and turf nutrition for over a decade, I've dedicated countless hours to correcting soil and perfecting lawns. Today, my expertise, backed by formal courses at UMass Extension Pesticide Education, allows me to offer top-tier lawn care services and advice. I am a fully licensed and insured lawn care applicator in Massachusetts, specializing in comprehensive turf nutrition, weed control, and lawn pest control. My license number is AL-0053865. Contact me at [email protected] or +1 (508) 500-8402.

10 thoughts on “[N-Ext] RGS™ Alternative | Root Growth Stimulant Substitute”

    • Hi Peter. Thanks for commenting. It’s best to mix and use sooner rather than later. These ingredients are in their purest form (dry soluble powders) so once applied to water (the activator) then it can begin to lose its potency. So if you can, I’d suggest mixing as close to the actual application date as possible.

      I let my mixes sit for about 12-24 hours before applying to help dissolve as much as possible. However, if everything is clean and stored properly, it can last for a few weeks. I have a garage refrigerator where I store any leftovers – these generally go in my flowers and landscape. Hope this helps.

      • I just re-read your post, so if I’m mixing for 4,000 square feet, I can just make enough concentrate with 2 oz (1/2 x 4) of extreme blend and 12 ounces of water. Does that sound right? Thanks!

  1. I just re-read your post, so if I’m mixing for 4,000 square feet, I can just make enough concentrate with 2 oz (1/2 x 4) of extreme blend and 12 ounces of water. Does that sound right? Thanks!

    • Hi Mike. I’d email them to confirm, but the biggest thing is keeping it air tight and dry. I’d say a hot garage in Florida might last 6-12 months so long as it’s dry and out of sunlight.


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