For a calm and relaxing feeling in the landscape, or to show off plants with yellow flowers, think about adding plants with blue flowers. Blue flowers are uncommon, but there are several annuals and perennials with blue or hints and tones of blue to enjoy in your garden.
Blue My Mind Evolvulus hybrid has silver-green foliage with blue flowers throughout the summer. The attractive annual reaches 6 to 12 inches in height and spreads up to 24 inches. It is easy to grow and performs best in hanging baskets or containers. It prefers full sun and tolerates heat.
Surfina Sky Blue Petunia hybrid has beautiful sky blue flowers with a hint of lavender. The fast-growing plant reaches 6 to 10 inches in height and spreads 8 to 10 inches.
This annual plant is heat-tolerant and a beautiful addition to patio pots. The flowers do not need to be removed after blooming to keep the plant looking nice.
Evening ScentsationTM Petunia (Petunia x atkinsiana) has indigo blue flowers that are fragrant with hints of hyacinth, honey, and rose.
The fragrance becomes more noticeable in the afternoon and evening. This annual blooms throughout the growing season and reaches 5 to 8 inches tall and 30 to 35 inches wide. It prefers a moist, well-drained soil.
The summer snapdragon, Angelface Dresden Blue Angelonia angustifolia hybrid reaches 18 to 24 inches in height and spread. The lavender-blue, 1-inch flowers are bicolor with a single white, angel-shaped petal on the downside.
Flowers are produced on spikes. This annual flowers all summer long with little care. Deadheading the old flower stalks is not necessary. It prefers to grow in full sun and well-drained soil and tolerates the summer heat.
Whirlwind Blue fan flower Scaevola hybrid is a tough plant that thrives in a hot, humid climate and can stand wind. The blue-purple, fan-shaped flower blooms throughout the summer.
The unique bloom looks good in hanging baskets or window boxes. This annual reaches a height of 8 to 12 inches tall and spreads 24 inches. It is also heat- and drought-tolerant.
Nemesia Bluebird (Nemesia fruticans) has a flower that is blue-purple. This annual is upright and fits well in containers as a filler. It reaches 10 to 12 inches tall with the same spread.
The plant may slow down with blooming in the hot summer but will increase flowering as the temperatures cool again. Nemesia grows in part sun to full sun.
Mealycup sage (Salvia farinacea) is an annual in our area but can reseed itself and return next year. “Fairy Queen” has dark blue and white bicolor flowers on spikes. The plant reaches 18 inches in height and 14 inches in width.
“Victoria” has deep violet-blue to deep blue flowers. The plants are compact, reaching 16 to 18 inches tall. They grow best in full sun and tolerate heat and drought. The flower spikes can be cut and used in fresh arrangements. Butterflies and hummingbirds are attracted to the blossoms.
Summer Wave Large Blue Torenia hybrid grows best in shade to partial shade. The large tubular-shaped flowers are two-toned with darker blue and lighter blue petals.
The carefree annual plant is covered with flowers all summer. The plant reaches 8 to 10 inches tall and 10 to 12 inches wide. Plant it in containers or in the ground.
“Johnson’s Blue” Geranium (Geranium) forms a spreading mound about 12 inches in height and 24 to 30 inches wide. The blue flowers appear in late spring to early summer. This perennial prefers morning sun and afternoon shade. It grows best in well-drained, moist soil.
False indigo (Baptisia australis) grows erect with stalks of blue, lupine-like flowers in spring. After the flower has faded, the seed pod becomes an inflated charcoal-black seed capsule.
The pods are desirable to use in dried flower arrangements. This plant was used by early Americans as a substitute for true indigo in making blue dyes. Use it as a specimen plant to display its clover-like, blue-green leaves. False indigo prefers full sun.
“May Night” (Mainacht) meadow sage (Salvia X superba or Saliva nemerosa) has deep violet-blue flowers produced on a stalk. The perennial plant reaches 18 inches tall, blooming in late spring and throughout the summer. It prefers well-drained soil and full sun. “May Night” tolerates heat and drought conditions.
“Best Bet” tall bearded iris (Iris germanica) blooms in the spring and may re-bloom in the fall. The large flowers have light blue standards, which are upright petals, and dark blue falls, which are downward-bending petals.
It prefers to grow in well-drained soil and full sun. The plant reaches 16 to 18 inches wide and 30 to 40 inches in height with the flower stem included.
Plumbago (Ceratostigma plumbaginoides) is a low-growing, 10-inch tall perennial. It has a central crown, making it ideal for a ground cover to help control erosion in small areas.
Morning sun and afternoon shade show off the marine blue, phlox-like flowers. It blooms in late summer through the fall, when the foliage becomes a beautiful bronze red. This plant needs well-drained soil.
For more information about plants with blue flowers, contact the Daviess County Cooperative Extension Service at 270-685-8480 or email@example.com.
To find the plants mentioned above, look locally at nurseries and garden centers first; then check catalogs and company websites. Watch for plant sales held by garden clubs, societies, and the Western Kentucky Botanical Garden.
Annette Meyer Heisdorffer, PhD, is the horticulture extension agent with the Daviess County Extension Office. She can be reached by calling 270-685-8480.