Dianthus

You’ll see dianthus, or Sweet William, most often in whites, pinks, or reds, with single or double flowers. They resemble small shrubs packed with flower stems.

“Dianthus, either as perennials or annuals, are great for color,” says Lynn Ackerman, greenhouse manager and horticulturist at the Lyman Estate. “They can take a lot of cold weather and have wonderful, spicy fragrances.”

She notes that they’re also great for pollinators and should attract both butterflies and bees.

• Zone: 4 to 9
• Size: 10 to 24 inches
• Container Size: 12 inches or larger
• Care Requirements: Full sun, well-draining alkaline soil

Heather

Heather (Calluna vulgaris) typically has pink and white flowers, and it blooms heavily from spring to fall. In a container, the stems can spray over the edge, giving the blooms the perfect cottage garden look.

This plant also has evergreen foliage, which looks especially lovely when other flowers aren’t yet in full bloom. “Plant in the sun to partial shade, and let it get a little dry between watering,” says Ackerman. 

• Zone: 4 to 9
• Size: 12 to 24 inches
• Container Size: 12 inches or larger
• Care Requirements: Full sun to part shade, sandy well-draining soil
  

African Daisies

African daisies (Osteospermum) come in all sorts of colors, from pinks and whites to purples and yellows. There’s also a stunning variety of patterns and petal shapes to choose from.

“They’re so charming and striking and add the perfect pop of vibrance to any container,” says Laura Janney, garden designer and founder of the Inspired Garden. “The contrasting color varieties help break up the pot, and the green leaves are shiny and lush.”

African daisies are sensitive to frost and need full sun to show their best blooms. The only tricky part? Make sure they’re evenly moist and not overwatered. “Keep them deadheaded for a longer bloom period,” says Ackerman. “They put on a good show.”

• Zone: 9 to 11
• Size: 12 to 24 inches
• Container Size: 20 inches or larger
• Care Requirements: Full sun to part shade, moderate to well-draining soil

Violas

If you’re looking for a flower with a fantastic scent that tolerates cold well, then violas should be at the top of your list. Because they bloom in early spring, they’re a great companion plant for tulips, as their relatively small size complements taller tulip stems.

“Violas come in bright showy colors, like blues, oranges, reds, and yellows,” says Ackerman. “And if you keep them deadheaded, they will bloom into the heat of the summer.” However, these small plants need to be well-watered in order to look their best.

• Zone: 6 to 11
• Size: 6 to 12 inches
• Container Size: 12 to 20 inches
• Care Requirements: Full sun to part shade, well-draining soil, medium to heavy watering

English Daisies

Though English daisies (Bellis perennis) and African daisies both belong to the aster family, there’s a distinct difference in that the former are much more compact, and they can be fairly cold hardy.

“They’re cute, showy little flowers, and are low-growing for the front of containers,” says Ackerman. “They tolerate a lot of cold, and can be planted in the garden, if you ever want to transfer them.”

English daisies have less of a color range than African daisies, but are still a delight in the spring. Make sure to keep them deadheaded for more blooms through the summer.

• Zone: 4 to 8
• Size: 4 inches to 8 inches
• Container Size: 10 inches to 20 inches
• Care Requirements: Full sun, well-drained soil, keep evenly moist

Snapdragons

Though snapdragons are short-lived, they make for an amazing display. And if you deadhead these flowers, well, you’ll get blooms for much of the season.

“There is simply no other flower like the snapdragon—they provide such a whimsical touch to your containers,” says Janney. “For spring, we use cold-tolerant varieties like Snapshot or Snaptini.”

• Zone: 7 to 10
  
• Size: 12 to 36 inches
  
• Container Size: 20 to 30 inches
  
• Care Requirements: Full sun, medium watering, well-drained soil

Ranunculus

“Nothing is more of a showstopper in a container than a ranunculus,” says Janney. These vibrant flowers come in a range of colors and heights and look “soft, yet defined, and charming,” she adds.

However, ranunculus can be sensitive to heat and humidity. So, if you live in a cooler climate, then you’ll have blooms for a bit longer in the season. “Simply deadhead the spent blooms,” says Janney. “And once it gets too hot, you can add another flower in its place.”

• Zone: 8 to 10
  
• Size: 12 to 24 inches
  
• Container Size: 20 to 30 inches
  
• Care Requirements: Full sun, medium watering, well-drained soil

Pansies

In the same family as violas, but with much bigger blooms, pansies come in just about every color. “They’re staples in any spring pot that I design,” says Janney. “They make a great filler and have such a range of colors.”

Like violas, pansies are also very cold tolerant, which means if you get a sudden cold snap, then you’re not completely out of luck. They do need full sun, however.

• Zone: 6 to 10
  
• Size: 6 to 12 inches
  
• Container Size: 20 to 30 inches
  
• Care Requirements: Full sun to part shade, medium watering, well-drained soil