If you have clay soil on the heavy side, you may have drainage issues, so be careful you don't over-water. Also, don't plant any annuals that prefer drier conditions (what immediately comes to my mind NOT to plant is annual vinca and portulaca).

I joined a rose club, and the speaker said soaker hoses get clogged. Still I really need something like that myself but I suppose I could hook up a sprayer instead and just not spray during the heat of the day. Sometimes last year I HAD to water in the heat of the day even after a good morning soaking and then again at night.

Mulch will work well if you put in plants that are already started, but I think it might be difficult to work around if you are sowing seeds directly into the ground. I'm doing a mixture of both.

I guess if you see the water is not soaking in fast enough or things are getting waterlogged, you could adjust the timer.

For spot watering in smaller areas, somebody suggested poking a hole in the bottom of a gallon jug and letting it drip. I tried that and it seemed to work ok. I'll probably resort to that, too, but it won't look so good; it's only temporary.

FYI: the black soaker hoses made from some sort of recycled material work very well. No clogging. One end is open, where you connect the hose; but you can cap it when the hose is not connected.