Parameters
Status
Interpretation
pH
< 5.5
Highly acidic
5.5 – 6.5
Acidic
6.5 – 7.5
Neutral
7.5 – 8.5
Alkaline
> 8.5
Highly alkaline
EC
(dSm-1)
< 0.8
Normal for all crops
0.8 – 1.6
Critical for salt sensitive crops
1.6 – 2.4
Critical for salt tolerant crops
> 2.4
Injurious to all crops
Parameter
Unit
Low
Medium
High
OC
%
< 0.50
0.50 – 0.75
> 0.75
N
kg ha-1
< 272
272 – 544
> 544
P
< 11.2
11.2 – 22.4
> 22.4
K
< 137
137 – 337
> 337
S
< 22.4
22.4 – 45.0
> 45.0
Ca
mg kg-1
< 150
150 – 300
> 300
Mg
< 50
50 – 100
> 100
Na
N.A
Limit
Zn
Cu
Fe
Mn
B
Very low
0-0.5
0-0.1
0-2
-
0.5-1
0.1-0.3
2-4
0.5-1.2
< 2.0
1-3
0.3-0.8
4-6
1.2-3.5
2.0
3-5
0.8-3
6-10
3.5-6
> 2.0
Very high
> 5
> 3
> 10
> 6
Pb
< 300 mg kg-1
Safe limit
Ni
< 75 mg kg-1
Cd
< 3 mg kg-1
Cr
< 150 mg kg-1
Sufficient
Bacteria
1 x 101 - 1 x 102
1 x 103 - 1 x 104
> 1 x 105
Fungi
1 x 101
1 x 102
> 1 x 103
Azotobector
1 x 103
> 1 x 104
Rhizobium
Phosphate
Solubilizing Bacteria
Azospirillum