Impatiens are annuals--plants that last for one year. Their name comes from the fact that the seedpods explode open, giving the impression that they are impatient to get the next crop started. Caladium is native to the Amazon jungles and is also known as the elephant ear plant. In warmer climates, caladium can be grown as a perennial. In warmer climates it will be an annual.
Impatiens can be red, scarlet, pink, white, rose or mauve and can grow to from 6 to 24 inches tall. The closer together they are planted, the taller they will grow. If they are planted farther apart, they will spread out and be shorter. Caladium has heart-shaped leaves that can be a combination of red, white, pink and green. They can grow from 12 to 18 inches in height.
Impatiens can be grown in every part of the country except for the coldest parts of the Midwest. Cold weather can seriously damage the caladium bulb. Caladiums need soil that is 70 degrees. From planting zone 7 and higher--areas where the average winter temperature does not go below 10 degrees in the winter--they can be left in the ground all year. Farther north, they need to be brought in for the winter or grown as houseplants.
Impatiens grow best in shade. They can tolerate some sun, but too much and they produce fewer flowers, are shorter and have smaller leaves. Caladiums grow best in partial shade. The can take full shade, but their color will not be as bright. Full sun is the worse environment. Both plants need a moist, well-drained soil.
Impatiens are good container, window box and border plants. Caladiums can be used outdoors as a ground cover or border plant. They also do well planted under large trees. This keeps the ground under the tree free from grass and eliminates a place where it is hard to mow. Caladiums are often used as a houseplant, in pots, hanging baskets and planters.
Impatiens is susceptible to bacterial diseases--bacterial fasciation and pseudomonas leaf spot. It is also susceptible to several fungal diseases--botrytis blight, downy mildew, fusarium root and crown rot, myrothecium leaf spot, phyllosticta leaf spot, phytophthora root rot, powdery mildew, pythium root rot, rhizoctonia root and stem rot, Southern blight and verticillium wilt. Impatiens can be attacked by viral diseases--cucumber mosaic, helenium S, impatiens necrotic spot, potexvirus, tobacco streak and tomato spotted wilt. Caladiums are susceptible to tuber rot, leaf spot and leaf burn. Diseases can be prevented by making sure the plants have enough air circulation so fungi do not have a moist place to grow. Bacterial diseases spread between plants like they do with humans. Cutting away damaged parts and disposing of them can help prevent the spread of the disease.