How to stop water flow in a siphon? I have assembled a small DIY drip-irrigation system for my terrace garden. Please have a look at the attached image.
I switch on a small pump to start the drip-irrigation system and then switch it off. But even after that, the water keeps flowing through the system and stops only when I physically lift the pump out of water.
How can I stop this water flow without requiring any physical action?

 A: The immersed pump my son used to water the garden from a rain water cistern has a top outlet over the level of the cistern water, dripping on a rose bush planted there. When the pump is turned off, this top small fountain head can be heard sucking air while the lower line empties.
I always check that the top drip works when the pump is on , otherwise there will be a siphon that will stop only when the cistern empties :).
So you just have to install a , maybe useless , drip over the height of the water,( and put a flower pot there :))
A: I would put a small "T" in the water line at the top of my tank, above the water line. Position it to pump water back in your tank when running. when the pump stops it should break the vacuum. Water goes back to your tank so it is not wasted.
A: Install a one way check valve in the vertical line at the exit of the pump discharge. Check valve will open in direction of the water flow due to pump pressure. When the pump is shut off, the valve will close either due to its weight or by a small spring when energy to pump is terminated. A shutoff valve at the crown will make the siphon completely controllable and the siphon will stay primed when the one way check valve at the outlet works effectively.
A: Beside my previous answer to use a check valve, another simple way is to extend the vertical line from the pump several inches above the top of the tank and at the top of that line turn the line 180 degrees downward. Install a tee connection in that vertical line at the point where you branch off to direct water to the plant pots and connect the line to the plant pots to it. When pump is turned on, water will flow from the pump and back into the tank due to the 180 degree return line and at the same time water will flow to the plant pots through the horizontal leg of the tee. When the pump is shut off, there will be no siphon effect.
A: Another alternative: make sure that you are using a positive displacement pump.  When such a pump shuts off, water cannot keep flowing through the pump.
Another possibility (from 9/02/2018): install a "T" at the point where the pump discharge line first goes horizontal.  Turn one part of the "T" straight up, and extend it by a few feet.  Leave this leg open to the atmosphere.  When running, water will rise up this vertical line a few inches, depending on how much pressure drop is in the line running to your flower pots.  When the pump is turned off, this line will drain, and the resulting air intrusion into the line will ensure that the siphon effect is "broken".
A: Can you just put a valve in the pipe? Or if the pipe is a rubber hose, just fold it in two and tie it. The kink in the hose will block it.
BTW, if you do that, after you start it you don't even need the water pump. You can just open the valve.
A: you can also add a vacuum breaker to the top of the piping circuit. this will vent the siphon to atmospheric pressure when the pump shuts off and stop the siphon flow automatically.
Vacuum breakers are commonly used in sprinkler system installations to prevent siphoning and can be bought in hardware stores. 
