RGS Root Growth Bio-Stimulant, Sea Kelp | N-Ext

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[N-Ext] RGS™ - RGS Stands for Root Growth Stimulant and that’s exactly what it does. This bio stimulant is packed with hormones from sea kelp that stimulate roots and stolons/rhizomes coupled with chelating humic acid.

  • One gallon covers up to 42,600 sq ft
  • Root Growth Stimulant (with Humic Acid and Sea Kelp)
  • Great for soil health and root stimulation
  • Available in multiple sizes*

Product Description:

[N-Ext] RGS™ - Root Growth Stimulant with sea kelp and humic acid is our primary bio-stimulant offering for use in lawns and landscapes. Formulated by John Perry of Greene County Fertilizer Co, RGS is the foundation of all Lawn Care Nut and Yard Mastery programs.

If you are new to spraying liquids on your lawn, this is a great one to start with. It won't "burn" the lawn or anything like that - and RGS is the best to start with anyway since it aids in soil health and stimulates roots in turf.

If you have challenges with your grass holding on during summer heat, getting RGS into the soil will help it through the stress. RGS is truly the backbone of the bio-stimulant program, hands down, and has the highest concentration of sea kelp hormones in the line. It was designed to increase rooting and decrease stress pressure caused by heat and drought. It will also feed microbial life in the soil which helps to optimize your fertilizer treatments.

"N-Ext" is the name of this line of products and N-Ext stands for "Nitrogen Extension." RGS, Root Growth Stimulant, is kind of like the "base layer" of that line because it contains humic acid and sea kelp, the two primary bio-stimulants we recommend. The biologically active material contains humic acid and sea kelp to aid in initial spring green-up, buffer and extend nitrogen release rates, and add oxygen to the soil profile for greater nutrient uptake.

*Available in multiple sizes: Size options on this item are quart, 1, 2 , 4, or 5-gallon. 

  • 1 Single Quart (32 oz) = covers up to 10,650 sq ft
  • 1 Single Gallon (128 oz) = covers up to 42,600 sq ft
  • 2 Gallon Pack (256 oz) = covers up to 85,200 sq ft
  • 4 Gallon Pack (512 oz) = covers up to 170,400 sq ft 
  • 5 Gallon Pack (640 oz) = covers up to 213,000 sq ft  

You can SAVE MONEY with the “mix and match” in our Build-a-Box options

For a list of all Greene County products, here is a link to the other options.

Application Information:
You will need to water in RGS if you apply with a backpack/pump sprayer, if you use an Ortho hose-end sprayer, here is a video with instructions. If you are using a quart hose-end sprayer, here is a video with instructions. 

RGS can be applied at any time during the growing season on all grass types, including the following:
Cool Season Lawns - Kentucky Bluegrass, Turf Type Tall Fescue (all fescues), Ryegrass.
Warm Season Lawns - Bermuda, St Augustine, Zoysia, Centipede, Bahia.

Custom timing and recommendations are available in our app. Click here to download.


42,600 sq ft at the low rate (3 oz/1,000 sq ft)
21,300 sq ft at the high rate (6 oz/1,000 sq ft)

Application  Details

Mix 3 oz- 6 oz per gallon of water in a backpack/pump sprayer and spray that evenly across 1,000 sq ft of lawn.

Apply every 30-45 days

Water-In  Instructions

Water into the soil within 24 hours with 1/4" of rainfall or irrigation.
Do not apply if your lawn is saturated. Rinse excess off sidewalks and driveways to avoid staining.

  • Label/Specs/SDS: RGS info
  • Link to Bio-Stimulant Guide
  • Package Includes: Quart, One, Two, Four Single Gallon(s), or 5-Gallon (two 2.5 gallon bottles) based on selection
  • Storage: Store in a cool dry place away from direct sunlight. The product will store for 2 years under warehouse conditions.

Shipping Information:

Shipping Costs

Included for most states within the U.S.
NO P.O. Boxes

State Restrictions
Alaska (AK), Hawaii (HI), and Oregon (OR)

Yes, a free sticker with this item

Typical Delivery Time

4 - 7 business days

Product Type

Liquid Concentrate

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