1. Soil pH?
How To Track!

2. Examples of Variation in Groundwater Quality
Well # 1
Well # 2
Well # 3
Soil Zone
Sand and Gravel Aquifer
Limestone or Granite Aquifer
Sandstone Aquifer

3. Irrigation Water Alkalinity concentrations (ppm CaCO3) from Florida25 20 15 10 5
Frequency %
<40
40–80
80-20
>400

4. The Goal Is To Achieve A Stable Medium pH Over Time

5. Plant Growth Cycle
Active Growth
Establishment
Mature

6. pH Drift Alkaline Water pH “Optimum” Range NH4+ fertilizers Time 8.5
8.0
7.5
7.0
6.5
6.0
5.5
5.0
4.5
Alkaline Water pH
“Optimum” Range
NH4+ fertilizers
Time

7. You Can Use the Water Hardness to Estimate Its Alkalinity
CaMg(CO3)2
Ca2+ + Mg2+ + 2CO32-
Dolomitic limestone
Hardness
Hardness and Alkalinity Generally Go Hand-In-Hand but They Are NOT One and the Same
You Can Use the Water Hardness to Estimate Its Alkalinity

8. mg/liter or ppm CaCO3 of alkalinity mg/liter or ppm bicarbonate
Alkalinity Terms
mg/liter or ppm CaCO3 of alkalinity
mg/liter or ppm bicarbonate
Milliequivalents alkalinity 1 2 3 4 5 50
100
150
200
250 60
122
183
244
305

9. The Effect of Water Alkalinity on Media pH and Acid Requirement
Sample A
Sample B
pH = 9
pH = 7
Alk = 50 ppm
Alk = 300 ppm
Increases growing medium pH
Little or no effect on the growing medium pH
One drop of acid to get pH 6
Ten drops of acid to get pH 6

10. Action Steps To Correct High Alkalinity
reverse osmosis
480
Alkalinity (ppm) bicarbonate
acid injection
180
120
acid fertilizer and/or
less lime
none

11. Testing The Soil Solution !

12. Pour Thru Method Simple technique for measuring pH and EC
Charts for recording pH & EC
Guidelines for crops
Procedures to keep on track

13. 6 or 8-inch saucers are adequate for collecting the leachate

14. Distilled Water Volumes
Pot Size ml oz
4 inch
5 inch
6 inch
6.5 inch
1 Qt
4 Qt
12 Qt 75
100
150
350
2.5
3.5
5.0
12.0

15. Flats: Use 50 ml Distilled Water

16. EC Comparisons 1:2 SME PourThru Indication 0 to 0.3 0.3 to 0.8
> 2.3
0 to 0.8
0.8 to 2.0
2.0 to 3.5
3.5 to 5.0
5.0 to 6.0
> 6.0
0 to 1.0
1.0 to 2.6
2.6 to 4.6
4.6 to 6.5
6.6 to 7.8
> 7.8
Very Low
Low
Normal
High
Very High
Extreme

17. Initial EC

18. Crop pH Ranges

19. Geraniums (6” pinched)
6.0 to 6.6
1/28
6.6 to 6.8
5/01
5.8 to 6.0