Marthastewart.com Feature: 15 Colorful Flowers That Will Brighten Up Your Garden

Cool Wave Pansy

Pansies add color to your garden with a variety of shades, from purple and orange to white and yellow. Zawada recommends the ‘Cool Wave’ cultivar, a purple, white, and yellow trailing plant for baskets, borders, and groundcover. "You can’t find anything with more flower color for your cool-season window boxes and containers than Cool Wave pansies!" she says. "If planted in the ground, it spreads almost as vigorously as it blooms."

Zone: 5
Size: 6 to 8 inches tall x 24 inches wide (trailing)
Growing conditions: Full sun; rich, well-drained soil

Mandevilla

This tropical vine shows off oversized, trumpet-shaped flowers in bright red, pink, and white during the summer, says Zawada. "Hybrid varieties offer even more color choices of apricot, peach, and yellow, and tend to be bushier," she says. "Grow this plant on a trellis or massed on its own in a planter."

Zone: 8 to 11
Size: Up to 20 feet tall x 15 feet wide
Growing conditions: Full to partial sun; rich, well-drained soil

False Indigo

False indigo, a drought-tolerant perennial, typically comes in blue or yellow—both fun choices for a colorful garden. But Decadence-brand hybrids offer shades in other hues. "Indulge in the deep, decadent Dark Chocolate for an added layer of depth, add drifts of candy floss clouds with Pink Truffles, or punctuate a planting with the sun-kissed bronze of Cherries Jubilee," says Regina.

Zone: 4A to 9B
Size: 36 inches tall x 36 inches wide
Growing conditions: Full sun; average, well-drained soil

Coral Charm Peony

Coral Charm peonies change color throughout their growing season, from raspberry to apricot to cream, says Regina. "The Coral Charm Peony has become a florist favorite over the years for the way the color shifts day-to-day, giving a feast for the eyes unlike any other," he says. "It’s a perfect addition to your cutting garden or mixed perennial border."

Zone: 3 to 10
Size: 24 to 36 inches wide x 24 to 36 inches tall
Growing conditions: Full sun; fertile, well-drained soil

Bat Face Cuphea

Plants don't come much more eye-catching than the Bat Face cuphea, with its orange-red "wings" and purple-black "face." "Don’t let the name scare you—whether a broadleaf evergreen perennial or annual addition in your zone, the cuphea is sure to bring saturation and conversation to your plantings," says Regina. "Blooming late spring through frost, the peculiar flower shape and gentle arcing habit is the perfect edge planting condition for your garden or containers."

Zone: 10 to 12
Size: 12 to 18 inches tall x 24 to 26 inch spread
Growing conditions: Full sun; average, well-drained soil

Lollipop Itoh Peony

Hybrid Itoh peonies are a mid-century icon in stunning shades. "A horticultural marvel of the 1960s, when first introduced in America the plants sold for over $1000 each," says Regina. "Singing in the Rain provides an ever-changing color story, Bartzella offers an electric yellow alternative to standard pinks, and, if you can’t decide, Lollipop will provide the best of both worlds."

Zone: 3 to 10
Size: 24 to 36 inches wide x 24 to 36 inches tall
Growing conditions: Full sun to partial shade; fertile, well-drained soil

Nasturtium

Bright nasturtiums provide a dose of color to your plate as well as your plantings. "Garnish your next salad with these vibrant, edible flowers that grow in shades of red, cherry, orange, peach, yellow, pale yellow, and burgundy," says Zawada. "With pretty, round green leaves, nasturtium are easy to grow from seed with dwarf bush varieties that can fit in any garden, or vining varieties that trail in window boxes or containers."

Zone: 9 to 11
Size: 12 inches to 10 feet tall x up to 36 inches wide
Growing conditions: Full sun to partial shade; well-drained soil

Blue Wonder Fan Flower

Though the fan-shaped flowers on this plant look delicate, Zawada says, they are hardier than they seem. "Available in white, blue, purple, or pink, this trailing annual plant is a knockout in hanging baskets, window boxes, or containers, and can be planted in the ground," she says. "It just loves hot and humid weather, as long as it’s well watered."

Zone: 10 to 11
Size: Up to 18 inches tall x up to 24 inches wide (trailing)
Growing conditions: Full sun to partial shade;