Building a Plant Watering System with an Arduino- Pumping Water

So now that we have a RTC connected to our Arduino, let's see if we can pump water!

First, we wanted to verify that our Peristaltic Liquid Pumps from  could do the job.  We bought some 1/16" ID silicone tubing from McMaster Carr, and we connected it to the small length of tubing that comes with the pump via a barbed tube fitting.  The longest run we used was 10 feet, and it had a vertical rise of 5 feet.   We ran the pump off a 12V power supply to verify it could pump water this distance.  Sure enough, it pumped no problem!

Now came the task of running the pumps off the Arduino.  It is a bad idea to hook any motor up to an Arduino directly, so we used Adafruit's outstanding Motor Shield.  In the new version that we sell, all you have to solder are some header pins!  We chose to use stacking header pins so we could add other things to our Arduino.
To use the Motor Shield, you simply stack the shield to the Arduino, supply power to the 2 pin terminal block, and then connect your motors (in this case pumps) to the shield.   Here is a picture of the whole thing.  Note that we connected two pumps to the motor shield, but you could connect up to 4.

So I want to be the first to admit that the way we coded this is not optimal.  At first we wanted to use a WHILE loop to have the pump run at a specific time, but for some reason this did not work.  So we decided to use an IF statement with a DELAY function.  Not perfect, but it did the job.  You can check out our Arduino sketch here.

Next all we had to do was run all the tubing.  We laid the tubing down in the flower boxes and then cut holes in the tubing where the water would spray out.  We tie-wrapped the end of the tube to seal it off.  We then ran the pump and watched where water came out.  You will want to do some experimenting to see where to cut and how deep to cut.

We got this all put together just before going out of town over July 4.  As you can see from the picture below, it worked pretty well!

For now we have a bucket that we have to fill once a week or so.  The next step will be to automate the filling with some kind of sensor that detects the level and actuates one of our water valves!