Getting started -- Your plant was grown in filtered light, not direct sun, so it should be acclimated to direct sun slowly. I recommend starting your plant in a 1-2 gallon pot and slowly move it from shade to sun over a period of a few weeks.
Transplant gently to avoid damaging the roots. Give no direct sun the first week after repotting to avoid wilting.
Watering -- Aim to keep the soil evenly moist most of the time. Don't allow the soil to dry out completely.
Sunlight & climate -- Established plants like part sun, although full sun can work in cooler conditions. In warmer climates, you may need to give it some afternoon shade.
I recommend protecting the plant from freezing temperatures. It can drop its leaves from light frosts, but reportedly can come back from the roots on mature plants after freezes of 25°F (-4°C) if mulched well.
Iochroma flowers best with cool nights (45-65°F), and daytime temperatures of 55-80°F. In hotter conditions, try to keep the pot shaded, perhaps by placing it inside a second pot made of clay.
Over about 40% humidity is best. If it seems to suffer from low humidity indoors, consider using an ultrasonic room humidifier.
Planting out -- Once your plant is around 2 feet tall, it may be planted in the ground, in suitable climates. If you'll keep it in a container, repot to a 3-5 gallon pot when the roots reach the bottom of the container. Repot again to a larger pot when it becomes rootbound. The size of the final pot depends on how big you let it grow. Larger plants need a lot of water and may dry out unexpectedly if undersized pots.
Fertilizing -- Feed about every 2 months during the growing season with a fertilizer that contains micronutrients (I use this).
It's normal for a few of the older leaves to turn yellow and die throughout the year, but if it seems excessive, the soil may be too dry down in the root zone. If you're unsure if the roots are moist enough, you can use a moisture meter. If you're certain the roots are moist, the plant may need more fertilizer.
Pruning -- Larger plants may be pruned to keep them shapely. Like with most bushes, removing lower branches encourages upward growth from the highest stems, while cutting back the tallest stem will encourage lower branching.
Pests to watch for -- Spider mites (tiny "dots" and webbing under the leaves), aphids, whitefly. Try using insecticidal soap before using stronger remedies, since some may harm the plant.
If you have any questions or problems, feel free to contact me.
Enjoy your plant!
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