Answer: If you only recently planted them, they are probably just trying to adjust to their new homes. When they do, they should perk up. If they have been planted for a few months, the dropping leaves could indicate heat stress or exposure to too much sunshine. You might try shading them from hot afternoon sun to see if that makes a difference. You didn't identify the plants so I can't guide you as to how much sun or shade they require or how much water they prefer. Wish I had more suggestions to offer.
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