I reccomend this method often as it is cheap and easy to do but it seems most shy away from it. What you need is a garden hose timer, a pump sprayer, tubing, misting nozzels, and connectors.
You should be able to find all this in your local home depot but if you have trouble with connectors or the misting nozzels then check out barrs.com.
What you do is cut the wand off the pump sprayer, use connectors to connect the tube from the pump sprayer wand to the garden hose timer inlet. Then use connectors to attach the outlet end of the garden hose timer to the 1/4" tubing and finaly to the misting nozzels. I believe barrs.com also has sort of a diagram for this method as well. It is pretty cheap with the greatest expense being the garden hose timer. I bought a digital one and it cost me about $30. To give you a reference of capacity ...
I used this setup with 4 nozzels from barrs attached to a one gallon pump sprayer. I set my on times for 3 times a day for about 1-5 mins. I filled the sprayer once a week and pumped it in the middle of the week.
For your setup you could easily use a 2 gallon sprayer with similar on intervals and you would probably use less nozzels. You would probably be fine for a good week and a half to two weeks without touching the system.
Compared to a pump driven system which usually costs upwards of $300 I think this is a deal.
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- Jason F.