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Water Calculator

Download the Amador County Master Gardener Plant Water Requirement Calculator to determine how much water your plants and trees actually need.  The program uses Excel 2007. The third worksheet tab at the bottom of the page is a Mulch Calculator.

  1. Expand page to full screen.
  2. Click on first Worksheet Tab at the bottom of the page.
  3. Choose a plant or tree you would like to know the watering requirements for and enter the canopy diameter in feet OR area of canopy in square feet
  4. Choose between the "water use" options and enter one
  5. Enter 50 for % of available soil moisture or a different percentage (for more experienced users)
  6. Enter the root depth in feet ( a helpful list is provided)
  7. Choose the soil type that most closely matches your soil and enter it.
  8. Enter the percentage based on your plants microclimate (refer to list)
  9. Enter the month of year (January = 1, December = 12)
  10. Enter percentage of irrigation loss due to inefficiency
  11. Read the amount of water to be given to this specific plant or tree in inches or gallons/week.
  12. Click on second worksheet tab at the bottom of the page. Complete cells B4, B5, & B6. Additional information is at bottom of the page.