Answer: I think your Angel's trumpet is just going through a little transplant shock. As soon as the roots become established it will produce healthy new growth. If it is small and you can temporarily protect it from hot afternoon sunshine, it will help. Aside from that, keep your plant watered well (twice a week deep watering while the temperatures are hot, then once a week when temperatures cool). Give your new plant a few weeks to adjust and you should see some healthy new growth.
Best wishes with your garden!
Q&A Library Searching Tips