Cotton
Monitoring Cotton for Nitrogen Needs, Cooperative Extension Service Leaflet
559, University of Arkansas, Division of Agriculture and U. S. Department
of Agriculture, Cooperating.
Nitrate Nitrogen in Petiole, mg/Kg (ppm)
|
Weeks after First Bloom
|
Sufficient Range
|
|
First Bloom
|
12,000 - 29,000
|
|
1
|
10,000 - 28,000
|
|
2
|
7,000 - 24,000
|
|
3
|
5,000 - 20,000
|
|
4
|
4,000 - 16,000
|
|
5
|
2,000 - 12,000
|
|
6
|
1,500 - 7,000
|
|
7
|
1,000 - 4, 000
|
|
8
|
500 - 2,000
|
Sabbe and MacKenzie. 1972. Plant Analysis: Cotton. pp. 302 - 308.
Sufficiency ranges for nutrient in cotton leaves
|
Element
|
Arkansas
|
Georgia
|
|
N (%)
|
3.00 - 4.30
|
3.75 - 4.50
|
|
P (%)
|
0.30 - 0.65
|
0.30 - 0.50
|
|
K (%)
|
0.90 - 1.95
|
2.00 - 3.00
|
|
Ca (%)
|
1.90 - 3.50
|
2.25 - 3.00
|
|
Mg (%)
|
0.30 - 0.75
|
0.50 - 0.90
|
|
Mn (ppm)
|
30 - 300
|
50 - 350
|
|
Fe (ppm)
|
30 - 300
|
50 - 250
|
|
B (ppm)
|
20+
|
20 - 60
|
|
Cu (ppm)
|
|
8 - 20
|
|
Zn (ppm)
|
20 - 100
|
20 - 60
|