Soil -- Iochroma likes well-draining soil. I use a mix of 1 part coco fiber and 1 part perlite. An alternate mix is 2 parts quality potting soil to 1 part perlite or coarse horticultural sand.
You can start it in pot about 1 quart in size, or about 5 inches wide. In hotter climates, use an oversized pot.
Transplant gently to avoid damaging the roots. Give no direct sun the first week after repotting to avoid wilting.
Watering -- The first month, make sure the original soil ball stays moist, not just the surrounding spoil. After that aim to keep the soil evenly moist most of the time. Don't allow it to dry out completely.
Light -- Your plant was grown in filtered light, not direct sun, so start it in bright, filtered light. After 1-2 weeks, give it about an hour of morning sun, watching for wilting. Increase the light by about an hour each 1-2 weeks. If it wilts, reduce the sun until its roots grow bigger.
Established plants like part sun, although full sun can work in cooler conditions. In hotter climates, you may need to give it some afternoon shade.
I recommend protecting it 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.
It seems to flower best with cool nights (45-65°F), and daytime temperatures about 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.
Repot to a 1-2 gallon pot after 2-4 months. The size of the final pot depends on how big you choose to let it grow.
Fertilizing -- Feed about every 2 months during the growing season with an all-purpose fertilizer that contains micronutrients.
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 probe. If you're certain the roots are moist, the plant may need more fertilizer.
Pruning -- Like with most bushes, removing lower branches encourages upward growth from the highest stems, while cutting back the tallest stem will encourage lower branches to develop.
Pests to watch for -- Spider mites (tiny "dots" and webbing under the leaves), aphids, whitefly. Try using insecticidal soap spray before using stronger remedies.
If you have questions or problems, feel free to contact me.
Enjoy your plant!
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