Plan your beds by "watering families" so plants with similar watering requirements are on the same timer. You won't kill the tomatoes while drenching your radishes. Keep in mind drip irrigation will prevent problems caused by splashing water on the leaves, uses less water and targets the plants specifically. I use 1/4" poly soaker hose on the veggies and individual drippers on each ornamental according to their water needs. For veggies that are neighbors with dissimilar water needs, everyone in that bed gets watered once a week and I hand water the thirsty guys again on Wednesday (you pick the day). Personally, I use battery powered timers and solenoid valves with compression fit poly hose and have no problems. You can change the configuration quickly and change the dripper size as the plants grow if needed.

i've had good luck with the pvc pipe with small (1/16?) inch holes. i lay down mulch first with mulch on top to keep the water stream under control. pvc is pretty cheap compared to drippers and seems to work ok for me.