Nutralene + Polymer Coated SCU 85% SRN 90-120-Day Nutrient Release at 70°F (21°C)

Suståne 18-1-8+Fe with Nutralene + Polymer Coated SCU

Suståne 18-1-8 plus Iron is a two-part blend with four-way release of nitrogen for lawns, containers and landscaped areas.  The most economical coverage of any organic based fertilizer.  18-1-8 is for topdress only and should not be incorporated into substrates or soil blends.

Professional Grade 

Suståne products are derived from biologically stable humus-rich compost and contain both water soluble nitrogen (WSN) and slow release nitrogen (SRN), beneficial microbiology, and all 17 elements essential for plant photosynthesis. With a near-neutral pH, a low salt index and low ammonium nitrogen percentage, Suståne will not cause seedling stress or plant fertilizer “burn”. Suståne products increase soil cation exchange capacity (CEC) by supplying humates and stable organic matter. Suståne’s organic and blended natural fertilizers provide all soil types with 

Benefits of Suståne 18-1-8+Fe CRF
  • Suståne 18-1-8+Fe is the longest lasting slow release nitrogen fertilizer made by Suståne.
  • Combines 4 different forms of nitrogen: 3 types of slow release including Suståne Organic N, PCSCU, methylene urea and 1 form of quick release nitrogen from ammonium sulfate
  • 15.3% (85% of total N) is slow release nitrogen
  • 18-1-8+Fe is extremely safe and will not burn or discolor plants and turfgrass 
  • Uniform particle size allows for even application
  • Long lasting Suståne 18-1-8+Fe provides steady, slow growth with excellent color for up to four months
  • Also used as topdress fertilizer for carry over nutrition in containerized nursery plants and perennial shrub beds (Please see recommended application rates in the Suståne Natural Base Fertilizers for Nursery, Greenhouse & Landscape technical brochure.)
12 - 16 week release rates

The controlled release portion of the material is made from industry leading polymer coated sulfur coated urea.  Nutrient release rates from Suståne 18-1-8+Fe are based on soil or substrate temperature and microbial activity. The sophisticated two mechanism release matches plant nutrient requirements over the production cycle and prevents dumping of nutrients. 

Applications and Rates

Container Topdressing Application Rates in grams

RATE  5" Std.
(12.7 cm) 
6" Std. 
(15 cm)
1 gallon
(3.8 L)
2 gallon
(7.6 L)
3 gallon 
(11.4 L)
5 gallon
(19 L)
7 gallon
(26.5 L)
10 gallon
(37.9 L)
15 gallon
(56.8 L)
LOW 2 3 4 9 16 25 35 43 46
MED 4 7 10 22 37 60 78 103 111
HIGH 5 4 16 32 57 92 131 159 170

Low Rate: Recommended for salt sensitive species; when concurrent with liquid feed; with production systems utilizing low leaching fractions (less than 10%); and when applied to heavy potting substrates (total porosity less than 65%).

Medium Rate: Recommended for use on medium feeding species; on most nursery stock and foliage plants; and when liquid feed is not performed.

High Rate: Recommended for use on heavy feeding species; with production systems utilizing high leaching fractions (greater than 20%); and when applied to light, porous substrates (total porosity greater than 80%).

Turf Coverage

50 lb. covers 9000 ft2 @ 1 lb. N per 1000 ft2 provides 44 lb. N per acre
22.67 kg covers 836 m2 @ 0.5 kg N per 100 m2 provides 50 kg N per Ha
5.5 lb. per 1000 ft2 / 2.8 kg per 100 m2

Cool Season Landscaped Areas

Parks, and Lawncare 
Apply 2-3 times per season. 
Spring and Fall: 5.5 lb. per 1000 ft2 (2.8 kg per 100 m2
Summer: 2.75 lb. per 1000 ft2 (1.4 kg per 100 m2

Warm Season Landscaped Areas

Parks, and Lawncare
Apply 5-7 times per season not exceeding 5.5 lb. per 1000 ft2 (2.8 kg per 100 m2) per application.


Store in a cool, dry place. Do not expose to moisture or extreme temperatures. 

*NOTE: Adjust fertilizer program for local conditions and requirements.

Item # 
Suståne 18-1-8
Package Size Units / Pallets
(2.8 mm - 1.4 mm) 
40-90-1175 (international)
50 lb. bags
1-ton tote 
22.68 kg bags 
40 bags / pallet
1 tote / pallet
44 bags / ISPM pallet 
18-1-8 FE Bulk Density

bulkdensity18 1 8


Total Nitrogen (N)
2.2% Ammoniacal Nitrogen
2.6% Water Insoluble Nitrogen**
11.0% Urea Nitrogen*
2.2% Other Water Soluble Nitrogen**
Available Phosphate (P2O5) 1%
Soluble Potash (K2O) 8%
Calcium (Ca) 1%
Sulfur (S) 6%
Iron (Fe) 1%

Derived from aerobically composted turkey litter, polymer-coated sulfur coated urea, methylene urea, ammonium sulfate, sulfate of potash, and ferrous sulfate. 
*10.5% slow-release urea nitrogen from polymer-coated sulfur coated urea. 
**4.8% slowly available nitrogen from aerobically composted turkey litter and methylene urea.