Sun Strength Testing Methods 

Your  sun guide for healthy and lush plants


There are three ways you can determine 

how much sun your yard gets.

  1. Single location / one test card.  This method is used to determine how much sun that area gets at that time of day.
  2. Multiple locations / multiple test cards.  Generally  used for comparative reasons to determine which location is best or to determine if  the sun strength  differs from  location to location.
  3. Single location / multiple test cards.  This is called Sun Averaging. This test method will determine how much sun that  location gets throughout the day.    


Method one  

Reverse fold the card creating a tent.  Place the card facing the sun for 10 minutes then  compare the test result to the color codes beneath the testing strip.  With this information  you are ready to purchase your plant that best reflects the needs of your plant.

Method two 

Reverse fold the cards - place in the locations you have selected for 10 minutes.  After 10 minutes compare your results to determine if  the amount of sun differs from each location or is consistent .  With this information you can now make your purchase.

The third Method is Sun Averaging.  

The testing cards are prepared  and placed the same way as in method 1 & 2 , but differ in the fact that you want to determine the amount of sun exposure for the entire day.  

After 10 minutes read the result and record the number appearing below the color code that matches your result.   Using the Sun Averaging method, your first test of three, should be taken approximately 2 hours after sunrise.

The second test should be a minimum of 4 hours later.   As before match the color and record the number.  
The third and final test, should be approximately four hours after the midday test and approximately 2 hours before sunset.  Record your third number, then add all the three numbers  and  divide by three to obtain the average daily exposure.  The  number average of the daily exposure will  be matched with the color code corresponding to that number.  With this information you are now ready to make your purchase.

    Helpful Hints

Set a timer for ten minutes at the start of each test.  This  way you will get a consistent 

time of the test.  Test on a sunny day.

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