How I Did It
I had to go around the raised bed so the pipe would come up in the walkway. This will save it from the lawnmowers and weed-eaters of the landscaping crew.
At the garden end, I turned the pipe up with a few elbows and put a 4-way manifold on the end.
To the manifold I attached 1/4" black drip irrigation tubing that ran to the end of each row of the garden. I attached drip emitter tube at the end of the black tubing. The emitter tube (brown in the pictures) has a small hole every 6 inches or so along the tube. I ran the emitter tubes down the center of each row of squares long ways. and secured them with landscape staples to keep them in place.
I hooked it all up and turned it on and it works great! From my tests it looks like I will need to run the system for about an hour a day. Each hole in the emitter tubing drips about half a gallon per hour. I am going to set it to come on at 5AM every morning to give the plants the water they need for the heat of the day.
The project took me about 2 hours and cost about $55 without the automated timer. $17.47 of that was the 100 feet of 1/2" tube.
I will clean up the drip tubing at the end of the growing season, but the big long tube underground should last for years, so even after the square foot garden is done, I can use that pipe to water our three raised beds either with a drip system or with a regular garden hose. That beats having the lug the hose over and then coil it back up in the heat of summer.
I also put up a piece of cattle panel for the tomatoes to climb. I probably should have done that a week or two ago because the tomatoes took some persuasion to lean over on the panel. I used some pieces of plastic grocery bag to tie them to the panel. While I was leaning them over I pruned off some of the lower branches of the oldest tomato plants to thin them out. I also pruned off some of the bottom leaves that were in the dirt. They were starting to show signs of blight. Getting rid of them will help keep the blight from spreading up the plant, or at least delay it.