Colorful Zinnias
Colorful zinnias in the garden

Not all flowers bloom all summer. Some naturally bloom for just a few weeks out of each season, while others fizzle when the weather starts to sizzle. To maximize color from the day you plant until frost ends the prime growing season, look for annual flowers – and heat-tolerant ones at that.

Annuals are those that go through their entire life cycle in one season. You plant them in spring, they flower in summer, then they die when (or soon after) temperatures drop below freezing in fall. Perennial flowers, on the other hand, are ones that come back year after year. But the tradeoff is that most of these bloom for only 4 to 6 weeks. Even among annuals, some perform much better than others. Here are a few good annuals that can take the heat of summer:

Purple Angelonia
Annual Vinca
Annual vinca

In full sun:

  • Angelonia. Flowers look like little orchids and bloom in purple, pink, white or blue-purple on
    12- to 18-inch spikes.
  • Euphorbia. Plants grow in rounded mounds and produce dainty white flowers that look like baby’s breath.
  • Petunia. New varieties bloom much heavier than Grandma’s kind. Among the best are the Wave, Supertunia, Surfinia, Famous, Suncatcher and Sanguna series.
  • Vinca. These take heat better than just about any flower and bloom on foot-tall plants in red, pink, white, rose or lavender.
  • Zinnia. Newer dwarf types such as the Zahara and Profusion series bloom all summer in hot orange, red or yellow without the disease and flopping of older, taller types.
Begonias in the garden

In shadier spots:

  • Begonias. These have glossy leaves and flowers of pink, red, rose or white. Dragon Wing types are especially showy, growing 2 feet tall and wide.
  • Coleus. The season-long color comes from the bright leaves, which range from red to gold to lime with assorted patterns and blends of each.
  • New Guinea and hybrid impatiens. Sidestep the mildew disease that often kills old-fashioned impatiens and go with the bigger, bushier and disease-resistant New Guinea types or hybrid versions such as Bounce and SunPatiens.

No matter which flowers you grow, you’ll get the best performance by keeping the soil consistently damp throughout the summer. Annuals are also “hungry” plants that benefit from regular feeding with a granular fertilizer every 4-6 weeks and even more often for potted flowers.