Answer: If other plants are thriving in the same bed, I suspect the soil is okay (drains well, etc.) so the problem may be too much exposure to hot sunshine, or too frequent watering. Plant roots need oxygen as well as moisture to thrive. Your heavenly bamboo plants need to adjust to their surroundings, and deal with hot weather, all at once. In order to establish well, the plants should be watered deeply once (or twice) a week. Allow the soil to dry out slightly between waterings. To promote new growth, cut the nandina back. Choose a few of the upright stems and cut them all the way down to the crown of the plant (don't lop off the top or your plant will maintain that look until new stems grow to cover it up!) Water deeply once or twice a week to encourage deep root growth. Once your nandinas become established they will grow wonderfully well for you. If they don't perk up within a few weeks and the site is receiving hot afternoon sunshine, you may want to consider moving your nandinas to a site with some shelter from hot afternoon sun.
Good luck with your garden!
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