21-4-8, 12-14 M

Economical choice for general purpose outdoor production

21

N

4

P2O5

8

K2O
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The Poly-S technology in Osmocote Blend 21-4-8 ensures that nutrients are delivered at a constant rate regardless of climate or temperature swings.

  • Consistent release and accurate longevity across multiple temperature ranges

  • Highly efficient nutrient delivery promotes robust growth and maximum economy

  • Dual coatings reduce nitrogen leeching and decompose with minimal environmental impact

  • Fortified with STEP Hi-Mag micronutrients

  • Can be incorporated into growing media or surface-applied in the container

Longevity at average media temperature

60 ̊F (15 ̊C)70 ̊F (21 ̊C)80 ̊F (26 ̊C)90 ̊F (32 ̊C)
14-16 months12-14 months8-9 months7-8 months

 

 

Surface application (grams)

Common container
volumes		Approx. containers
per cubic yard1		LowMedHigh
1 quart850568
2 quart400101417
1 gallon trade300131823
1 gallon210182632
2 gallon trade125314454
2 gallon102385367
3 gallon70557897
5 gallon5274105131
7 gallon35110156195
1May vary depending on container brand, media, and fill method.

 

 

Large container volumesSurface area
in square feet		LowMedHigh
10 gallon (17" diam.)1.4133188235
15 gallon (17.5" diam.)1.5143202252
20 gallon (21" diam.)2.3219309387
25 gallon (22.5" diam.)2.8267377471
30 gallon (26.5" diam.)3.8362511639
45 gallon (30" diam.)4.8457646807
65 gallon (30" diam.)4.8457646807
100 gallon (36" diam.)7.16859471210
200 gallon (48.5" diam.)12.8123417082181
24" box4.0381538673
30" box6.255968411051
36" box9.085812111513
48" box16.0152521522690
For containers not listed, multiply surface area by:95135168

 

 

Incorporation

LowMedHigh
Pounds per cubic yard8.512.015.0
Kilograms per cubic meter5.07.18.9
Grams per liter5.07.18.9

 

 

Landscape

LowMedHigh
Pounds per 1000 square feet9.519.028.5
Kilograms per 100 square meters4.69.313.9
Pounds of N per 1000 square feet2.04.06.0

 

 

Approximate Volume Measurements

 

ICL spoons

#1#2#3#4#5#6#7
Grams9131634456689

 

 

Conventional measures

1 tsp.1 tbsp.1/4 c.1/3 c.1/2 c.1 c.
Grams5146283125249

1
Verify product analysis, longevity, and rate for plants in your production system (for assistance, contact your regional ICL Territory Manager or call ICL Customer Service at 800-492-8255)
2
Consult rate tables printed on bag labels and product sheets
3
For incorporation, blend into growing media to ensure uniform distribution of fertilizer
4
Do not over-mix (doing so could damage fertilizer coating)
5
Growing media should be used within two to four weeks after incorporating fertilizer
6
For top-dress applications, spread fertilizer evenly on container surface (avoid piling fertilizer directly against plant stem)
7
Irrigate after application (irrigation frequency and volume should be adjusted during the crop production cycle according to crop type, environmental conditions, and desired soluble salt levels)
8
A product trial is recommended before adopting a new fertilizer program or making full-scale changes to standard cultural practices (test several rates on representative plant types)
9
Use caution when applying to plants being over-wintered under cover (if you can't monitor soluble salts and/or adjust irrigation practices, avoid Fall and Winter applications
10
Store in a clean, cool, dry place

Brand details

This product is part of the Osmocote Blend, Poly-S portfolio

Poly-S release technology delivers nutrition at a constant rate regardless of climate variations.

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