Embedded Gardening




We planted some tomatoes. But then we wanted to take a vacation. The easiest thing to do would have been to ask a friend to water or get a timer with some drip tubing.

Simple timers like this are available at Home Depot and Amazon.

There are fancier WiFi Enabled ones too:




Also there are these pumping systems that require containers of water which they pump from. Does this seem crazy to anyone else? Is the reasoning behind this to limit damage when watering indoors due to system malfunctions due to system errors? Is this to avoid accidental $1000 water bills for plumbed systems?



Another concern is how can I know that the system is working and really watering the tomatoes? I can point one of my Arlos at it to get a pretty good idea. While better, it's somewhat limited. If I want to see them all with one camera, I won't be able to look closely and see if the soil is damp.



Also, I'll bet I could find some industrial controllers. But looking around, what I found seemed expensive.

It seemed like a pretty good excuse to buy some parts and play around with some micro controllers and hardware!

The things I wanted it to initially do are:

1. Provide some sort of WiFi accessible interface.
2. Be small and power efficient.
3. Be able to turn water on and off for several tomato plants.
4. Have sensors for:
  • Soil Moisture (preferably for each plant)
  • Air Temperature (Humidity + others a plus)
  • Light brightness (not that useful, but still fun)
  • Water flow / usage.

I've already started on a lot of this, but to keep posts of reasonable size and snackable, I'll be posting and catching this blog up incrementally.

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