Pot size -- You may start your plant in a 1 gallon pot, and then transfer it to a 3-5 gallon pot when it's rooted through, 6-12 months later. Use a pot with drainage holes.
Soil -- Like most Impatiens, Impatiens claeri likes moist, fertile, well-draining soil. A typical mix is 1 part potting soil to 1 part perlite or coarse horticultural sand. An alternate mix is equal parts of coir fiber and perlite, with some slow-release fertilizer mixed in.
Transplanting -- Transplant carefully to avoid breaking apart the soil ball. Don't pack the soil down after repotting. Impatiens sometimes wilt after being repotted, and if yours does, simply cover it with a plastic bag that has a dime-sized hole in it. Each day make another hole in the bag. After a week you should be able to remove the bag.
Watering -- Aim to keep the soil evenly moist most of the time, but not soggy. If you're unsure how moist the soil is, use a moisture meter probe, which are sold inexpensively at garden and hardware stores. Don't let the pot sit in a tray of water.
Lighting -- Impatiens claeri is tolerant of a wide range of lighting, from bright shade to sun. It seems to prefer either filtered sun throughout the day, or bright shade + morning sun. It does not need a lot of light to thrive. In warmer temperatures, give it afternoon shade and keep the pot shaded.
Your Impatiens was grown in filtered light and should be acclimated to direct sun slowly, over a period of 2-3 weeks.
Climate -- Impatiens claeri is happiest between about 50 and 85 degrees F (10-29°C). It might tolerate warmer temperatures if nights are cool. It can tolerate temperatures close to freezing, but it may perish from freezing temperatures. I have heard of it regrowing from the roots after being frozen to the ground, but i wouldn't count on this. It's best to protect it from all frost.
Over about 40% humidity is recommended. Indoors, if the air is too dry, consider using an ultrasonic room humidifier, sold at home improvement stores and thrift shops.
Fertilizing -- Your Impatiens likes average amounts of fertilizer. Feed about every 2 months with a slow-release (pelleted or organic) fertilzer.
It's normal for an older leaf to occasionally turn yellow and drop, but if it seems excessive, the soil may be too dry down in the root zone, or the plant may need more fertilizer, particularly nitrogen.
Pruning -- Feel free to shape your plant as it grows. If you want a tall, tree-like look, remove some of the lower side branches. If you prefer a compact, dense plant, pinch off the growing tip of a branch, and it will respond by growing side branches.
If your plant gets very tall, the branches may need support to keep from falling over.
Pests to watch for -- Scale (little brown disks on the stem - very hard to see!), aphids, spider mites (tiny "dots" under the leaves), whitefly, mealy bugs.
If you have any questions, feel free to email me.
Enjoy your plant!
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