Answer: I'm thinking you're overwatering your new hollies. They need about an inch of water per week for healthy growth and the soil needs to dry out slightly between waterings. I don't know what size emitters you are using but even a .05 GPH is too much if you leave the system on for an hour each time. Try taking your hollies off the drip system for now - at least until they are established and hand watering once a week, allowing the water to slowly penetrate to the root system. About one inch of water per plant per week should be your goal.
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