Then he did an experiment. He let the system go dry and it took three and a half hours before the cherry tomato plant showed any signs of water depravation, i.e. wilting. So he set the timer to one minute of watering, and one hour of drying in between each watering. The plants took off like gangbusters!

is this using rockwool , this experiment...

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In the End, we will remember not the words of our enemies, but the silence of our friends.

Martin luther king.