16 4 8MED50lb 600wide

Suståne® 16-4-8 180 Day Natural Organic + Coated Controlled Release Fertilizer

Designed for Professional Nursery, Greenhouse and Landscape Applications
180 - 210 Day Nutrient Release at 70º F

Label Spec Sheet MSDS


Suståne 16-4-8 was developed as a combination fertilizer to provide nursery stock with a time released 4-1-2 nutrient package blended with a 50% Suståne humus rich, premium organic base. Suståne 16-4-8 Nursery Fertilizer is available in both 180-day and 120-day release profiles to meet the needs of your production cycle. Suståne 16-4-8 Nursery Fertilizer is derived from aerobically composted turkey litter, polymer coated urea, polymer coated MAP, and polymer coated potassium nitrate.

Recommended Use:

Suståne 16-4-8 is perfect for production of perennials and woody ornamentals. Nursery producers can use Suståne 16-4-8 to grow beautiful Azalea, Holly, Weigelia, Crape Myrtle, Cotoneaster, Boxwood, Spiraea, Salvia, Hibiscus, and Daylily.

Features of Suståne 16-4-8:

  • Suståne® 16-4-8 provides 6-7 month nutrient release in containers.
  • Suståne® Organic+CRF produce predictable results, dependable performance and high quality plants.
  • Designed, tested and proven to provide equal or superior growth results compared to similar formulations (4-1-2 ratio) of nursery industry standards.
  • Suståne® Organic + SumicoatTM Controlled Release Fertilizers (CRF) are the new generation in environmentally friendly plant nutrition with minimal impact on the non-target environment.
  • Enhances soil-plant nutrient exchange increasing uptake efficiency.
  • Low burn potential, nutrients release gradually over time.
  • Suståne® 16-4-8 supplies all primary, secondary and micronutrients required for complete plant photosynthesis.

Benefites of Suståne 16-4-8

  • Rich in humic acids
  • Increases the nutrient and water holding capacity of the soil
  • Strengthens plants tolerance against hot dry conditions
  • Promotes greater root development
  • Improves buffering against changes in soil pH
  • Increases the soil’s ability to suppress plant pathogens
  • Increases soil porosity and stability for greater root development and water holding capacity

Always Safe for Plants, People and the Environment

  • Manufactured by Suståne in the USA at an EPA permitted facility.
  • Pathogen and weed free, no blood or bone products. Allowed for export to over 60 countries world wide..
  • Aerobic composting eliminates animal and rodent attraction to application site.
  • Contains naturally occurring beneficial bacteria and fungi that are necessary to begin nutrient life cycle in poor soil.
  • Suståne is fully composted eliminating the need for sterilization, permitting a healthy environment for beneficial microbial populations.

Suståne® Enhanced with SumicoatTM Controlled Release Fertilizer

SumicoatTM Controlled Release Fertilizers are polymer-coated controlled release fertilizers initially tested and developed for the rice production markets in several different climates in Japan. Sumicoat products have been used for years to release precisely the right amount of fertilizer to optimize plant growth. For the past several years Suståne has been evaluating different Sumicoat release products blended with Suståne organics to create the optimal nursery and greenhouse fertilizer combinations. Suståne and Sumicoat have been proven through years of research to provide the winning combination that will not under or over release..

Guaranteed Analysis

Total Nitrogen (N) 16%
0.5% Ammoniacal Nitrogen*
2.6% Nitrate Nitrogen*
1.5% Water Insoluble Nitrogen**
11.2% Urea Nitrogen*
0.2% Other Water Soluble Nitrogen
Available Phosphate (P2O5) 4%
Soluble Potash (K2O) 8%
Calcium (Ca) 2.75%
Magnesium (Mg) 0.75%
Sulfur (S) 1.00%
Iron (Fe) 0.25%
Manganese (Mn) 0.05%

Total Plant Nutrition

Humic Acid 5%
Organic Matter 45%
pH 6.8
Carbon:Nitrogen (C:N) 2:1
Bulk Density lb./cu. ft 42
Salt Index (scale 1-100) 4
% of Total N as Slow Release 90%

Derived from aerobically composted turkey litter, polymer coated urea, polymer coated potassium nitrate, polymer coated monoammonium phosphate, ureaform, feather meal and sulfate of potash
*14.1% controlled release nitrogen derived from polymer coated urea, polymer coated potassium nitrate and polymer coated monoammonium phosphate.
**1.5% slow release nitrogen derived from aerobically composted turkey litter, ureaform and feather meal.

Available Particle Sizes:

  • Medium Grade, 200 SGN (2.8 mm - 1.4 mm)


  • 50 lb. covers 8,000 ft2 @ 1 lb. N per 1,000 ft2 (44 lb. N per acre)
  • 22.67 kg covers 744 m2 @ 0.5 kg N per 100 m2 (50 kg N per hectare)


  • Apply 6.25 lb. per 1,000 ft2
  • Apply 32 g per 1 m2

Incorporating into Potting Soil Mixes and other Container Substrates:

Suståne 16-4-8 180-day provides constant release of nutrients for approximately 180-days when used with container substrates with average temperature of 70oF / 21oC. When determining application rates consider all cultural practices including irrigation, container substrate physical characteristics and growing environment.

Container Mix Application Rates:

Container Mix Rates by Volume
lb. per cubic yardkg per cubic meter
5 9 12.5 3.0 5.3 7.4

Landscape Application Rates by Area
lb. per 1,000 square feetkg per 100 square meter
10 18 24 4.9 8.7 11.7

Bulk Density of Suståne 4-2-2:

Container Mix Rates by Volume
Rounded Measure (Volume)Grams (weight)
Teaspoon (tsp)Tablespoon (Tbs)1 oz1/4 cup1/2 cup1 cup
3.1 9.3 18.6 7.2 74.4 148.8

Container Topdressing Application Rates in Grams:

Rate5" Std.6" Std.1 gallon2 gallon3 gallon5 gallon7 gallon10 gallon15 gallon
Low 5 8 12 26 46 74 105 128 137
Med 7 12 19 40 69 111 158 191 205
High 10 17 26 55 57 155 221 268 287

Low Rate: Recommended for use on 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 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%).

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%).

  • These rates are intended as guidelines. Suståne encourages a trial prior to changing any fertilizer program.
  • Do not steam sterilize container mix after fertilizer has been incorporated.
  • Do not store container mix more than two weeks after incorporating fertilizer. Plant material can be damaged from salt accumulation.
  • Monitor electrical conductivity (EC) of container substrate throughout production cycle.
  • If mix is stored longer than two weeks, leaching container mix may be required to remove accumulated salts.
  • Adjust application rate as needed.spec sheet