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Appendix 4
Greenhouse Media
Soluble salt guidelines for greenhouse media using
various media to water ratios (Testing and Nutrition
Guideline, MSU Ag Facts Extension Bulletin E
-
1736,
September, 1983).
a
saturated media extract
b
1 part soil to 2 parts water
c
1 part soil to 5 parts water
Electrical Conductivity (mS/cm)
Comments
SME
a
1 to 2
b
1 to 5
c
Very low levels. Indicates
very low nutrient status.
0
-
.74
0
-
.25
0
-
.12
Suitable range for seedlings
and salt sensitive plants.
.75
-
1.99
.25
-
.75
.12
-
.35
Desirable range for most
established plants. Upper
range may reduce growth
of some sensitive plants.
2.00
-
3.49
.75
-
1.25
.35
-
.65
Slightly higher than desira-
ble. Loss of vigor in upper
range. OK for high nutrient
requiring plants.
3.50
-
5.00
1.25
-
1.75
.65
-
.90
Reduced growth and vigor.
Wilting and marginal leaf
burn.
5.00
-
6.00
1.75
-
2.25
.90
-
1.10
Severe salt injury symp-
toms with crop.
6.00+
2.25+
1.10+
Classification of Greenhouse Media