1. Taking Water Management to a Higher level
or how do you train someone to water correctly?
Will Healy
Senior Technical & Research Manager
Ball Horticultural Company

2. kills more seedlings & plants than anything else we do!
Incorrect watering
kills more seedlings & plants than anything else we do!

3. Plant Demand Water Consumption
Floral
Initiation
Flower
Expansion
Ship
Stage 1
Pinch
Stem
Elongation
Stage 2
Stage 3
Plant

4. PWS!* Pay to Water Pay when @Dry Target Paranoid Watering Syndrome
Dr Will, Dr Will
Help me please - I suffer from…..
PWS!*
Pay Target
Pay to Water
Paranoid Watering Syndrome

5. Water Knowledge Pyramid
Quantitative
aka
Data based
Qualitative
aka
Opinion based
Climate
Plant Demand
Where to Water
How Much to Water
When to Water-How Dry?
Language of Watering W1-W5

6. What is this?? What are you trying to do??5 1 2 3 4

7. Pyramid Level 4 Where to Water
3 Dimensional Space!
Edge
Middle
Depth
W2-3
W5-2
W3-5
W4-5
Highly Branched Root System
Top Horizontal Root System
Water Root System
Vertical Root System

8. Drying out a cell
Drying out a cell is due to evaporation of the water from the soil
Water loss is sigmoidal over time
Incremental loss is slowest at level 5 & 1
Incremental loss is linear with time at level 4-2
If water loss is g per day then the loss of 800 g (level 42) will take 2-4 days.

9. Non-Uniform Begonia
Note that dry down below the target dry levels (white line) of the early stages of development which caused the root damage early in production.

10. Horizontal Rooting (top wrap)
Why do we see top rooting with minimum roots at the bottom?
Even though the last days went 4→2 the first 5 days after germ (circle) stayed evenly moist which started the horizontal root development
Failure to dry keeps top wet (Blue)
Failure to go wet allows salts to build on bottom of plug (Red)

11. Watering Success Draw the roots to the bottom of the container.
Saturate to a level 4 (bottom drip)
Dry to a level 2
Train your watering pattern to a 4-2
It’s the drying that promotes rooting
Water to get to the next dry point

12. ‘Tools of the Trade’ 5 gpm 3 gpm 19 lpm 12 lpm 2 gpm 0.5 gpm 8 lpm

13. RH + Temp  VPD

14. What drives water loss from the container?B ET
Evaporation
Transpiration
Change in tray weight will predict the ET rate
Weigh the same container in afternoon & morning.
Night ET = afternoon-morning
Day ET = morning-afternoon
Night Water Loss
200+ gm – Rapid drying
gm – Ideal
gm – Too wet issues
< 50 gm – Tip abortion

15. Managing the Water in the Container
How much water (weight) is lost each day?
How much water (weight) is lost each night?
How much water weight must I add to reach the target weight tomorrow?
How much water weight must I add to get water to the bottom of the cell or pot?
It’s not the how wet or dry but how long does it take to get to the next watering time

16. Water Knowledge PyramidET
tells the
story
Climate
Drive the
roots to
the down
Plant Demand
Set your wet
target time
Where to Water
Set your
Dry target
How Much to Water
Qualitative &
Quantitative
When to Water-How Dry?
Language of Watering W1-W5