Answer: Brooms are reasonably adaptable plants so I think yours is just going through some transplanting stress. I'd cut back on the water to about twice a week. Brooms can grow in hot, dry places so you may be suffocating the roots by driving out the oxygen when you water so often. Give your broom a chance to adjust. When you begin seeing new growth, prune away the dead branches and it should recover quickly.
Best wishes with your garden!
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