Arduino Powered Vertical Garden

I started setting up a Vertical Garden in the back yard using PVC and landscape timbers. I plan to grow romaine lettuce and a few herbs for starters. At the moment there are just some plants I picked up at Home Depot for testing, I didn't bother to transplant them from the containers they came in for now. Eventually I plan to use net pots or net cups in the system and have a semi-hydroponic setup going. By semi-hydroponic I mean starting plants in small extremely fertle bundles of organic matter, wrapped in a mesh that's strong enough to keep the organic matter in place but weak enough to let roots grow out into a medium in the net pots. My plan is that the small amount of organic matter will be enough for water sprinkled on the system to leach out into the pipes and feed the rest of the roots. So all I'll have to do is setup watering automation and harvest once growth stunts.

Here's a couple of photos of the system at the moment. I originally went with foggers and a 12 port drip irrigation manifold, but there was not enough pressure in my house spigot to push the foggers. I experimented with some sprayers I had and they're wasting a lot of water because the spray pattern is too large. I have one basket mister on the system and it looks like the way to go. I'm thinking a 6 port manifold and 6 of those misters will work fine.

Now, the title does say "Arduino Powered" vertical garden, so I suppose I should get to the Arduino part. I haven't actually started on that part yet, though here are my plans with it. I'm going to hook at solar cell scavanged from a solar powered deck light to the analog input of the Arduino for use as a sun meter. The more voltage I see on that analog input, the brighter it is outside. I live in Florida, so it's always humid... The brighter it is, the more water I need to hit the plants with.

I was originally going to use a simple garden hose timer to water everything, but given I have the yard sprinklers on another Arduino Mega in the house anyways, I might as well hook this up as well.

Anyways, I'm having a tough time finding local suppliers of 3 3/4" net pots to fit in my 3 1/2" holes. So I'll have to order them online and wait for a bit. On the bright side, my Home Depot had Dig brand drip irrigation supplies on sale for about 80% off! 50ft rolls of 1/4" microtube for $0.99 instead of $4.99, score!