One of the best container plants for hot, sunny spots, angelonia produces beautiful spikes of mauve, purple, pink, blue, or white flowers all summer long. It's a strong performer in containers as well as landscape beds and borders. These colorful annuals are also available in tall upright and short bushy varieties so you can use them in a wide variety of garden settings. In the North, angelonia is grown as an annual; in frost-free regions, it's treated as a perennial. Most angelonia varieties grow between 12 and 18 inches tall. The plants also attract butterflies and bees.