Allowing new planting to go dry definately will affect the plant and shows up as some type of stress (wilitng, brown foliage etc) Hopefully you go to them soon enough so that any extensive root damage is avoided. Keep the area moist by allowing the hose to run slowly so you get a good ground soaking. you may need to dig around the plant a bit to see how far the water has gone down. You want a moist soil. Once that happens water again when the soil starts to dry and that can best be judged by doing a little digging. Too wet for too long and extended wet soils can also result in root death so you want to avoid that also.