How to Grow and Care for Columbine

Columbine (Aquilegia spp.) blooms are said to resemble jester's caps, and their effectiveness at attracting hummingbirds will certainly put bird watchers in a merry mood. This herbaceous perennial is an airy plant with attractive clover-like foliage. The blooms come in many colors, and most have spurs: long, narrow strips streaming horizontally from the back of each flower. This plant is generally planted in early spring. Established plants typically bloom for about four weeks starting in mid-spring.

Columbines are short-lived perennial plants, but if you let the flower heads go to seed rather than deadheading them, they will readily self-sow and might soon form a colony of plants when growing conditions are optimal. They have a moderate growth rate, and seeds germinate in about 20 to 30 days. Columbine plants are toxic to humans.

Columbine Care

Columbines are great re-seeders. Many gardeners save money by starting the plants from seed rather than buying them at the nursery in pots (although you will have to wait a year for flowers). Not deadheading will result in plenty of self-sown replacements.

These plants do not tolerate hot, full sun well; they decline in the summer. They prefer medium moisture, well-drained soil. However, once established, columbine plants are drought-tolerant perennials. These plants are perfect for rock gardens and woodland gardens. Their attractive foliage makes them suitable as edging plants, and they are also frequently used in cottage gardens.

Light

Partial shade is the standard recommendation for growing columbine, but this plant tolerates full sun in cooler climates and during cool spring days.

Soil

Grow columbine plants in well-drained humusy soil with a neutral to slightly acidic pH. Mix some compost into the soil before planting to provide them with rich organic material. They prefer sandy or loamy soil over clay because good drainage is key.

Water

Columbine requires moderate soil moisture, so apply water when the top inch or two of soil dries out. As young plants are becoming established, keep the soil evenly moist but never soggy. Established plants only need watering about once a week. Mulch the plants to conserve water in the summer.

Temperature and Humidity

Columbines are perennial in USDA hardiness zones 3 to 8, but choose a variety that's well-suited for your specific climate. The plants flower best in cooler temperatures. They don't tolerate excessive heat.

Fertilizer

Use a liquid, water-soluble fertilizer once a month during the growing season (spring to fall) to promote healthy foliage and better blooming. This plant requires phosphorus for healthy root development. Fertilizer too high in nitrogen can affect flower production; try using 5-10-5 NPK fertilizer, which is boosted in phosphorus.

Types of Columbine

• Aquilegia flabellata 'Nana': A dwarf cultivar with light blue and white bi-colored flowers; six to nine inches tall
• Aquilegia 'Crimson Star': Crimson red and white bi-colored flowers with long spurs; 24 to 30 inches tall.
• Aquilegia 'McKana Hybrid': Bi-colored flowers with long spurs in shades of blue and white, red and yellow, and combinations of pink and purple; plants are tall, up to 30 inches
• Aquilegia caerulea: Rocky Mountain columbine has grayish-green, fern-like foliage; very large white flowers with violet-blue sepals and yellow stamens; grows up to 24 inches tall
• Aquilegia vulgaris 'Clementine Salmon-Rose': A long-blooming variety with salmon-colored, upward-facing blooms that resemble the blossoms of a double-flowered clematis; 14 to 16 inches tall

Pruning

Prune columbine plants back to their healthy base leaves just after blooming. Doing so might promote a second set of stem growth within a few weeks enabling you to enjoy another wave of blooms later in the season. Columbines can be cut back to about one-half of their height after flowering to keep the plant attractive and green for the remainder of the summer.

Propagating Columbine

Columbine is best propagated by sowing seeds or by division. Columbine seeds can be directly sown in the garden in early spring or summer.

Columbine can be divided in the spring, once every two or three years. A divided plant remains vibrant and vigorous for many years. Columbine has deep roots, so if you must divide it, dig down deeply. Here's how to propagate by division:

1. You'll need a shovel or spade and a sharp knife.
2. With a spade or shovel, deeply dig in a circle around the plant to loosen up the plant from the ground.
3. Lift the plant out of the ground being careful not to break up the soil around the root system.
4. Work fast to divide and re-plant: divide the plant as quickly as you can with a sharp, sterilized knife. Try not to dislodge soil around the roots.
5. Replant one division into the same planting hole and backfill the hole with well-draining soil.
   

How to Grow Columbine From Seed

Propagating from collected seeds is the easiest way to grow columbine. After the flowers have faded and dried up, harvest the ripened seed pods left inside and break them open to collect the shiny black seeds. Store them in the refrigerator over winter. They need three to four weeks of cold before germinating, which ensures they will be ready to sow when the time comes. Plant them in the garden the following spring. Or you can let your columbines reseed naturally by not deadheading spent blooms

If you start the seeds indoors, plant them in moist soil by laying one to two columbine seeds on top of the soil mix and cover lightly with additional soil. Set them in a sunny location. The seedlings will emerge in three to four weeks. When the plants reach three to four inches in height, harden them off gradually, then plant them outdoors about ten inches apart.

Potting and Repotting Columbine

Plant each seedling in a medium-sized (ten inch) container. Container material can be plastic, clay, wood, or stone, but ensure the container has drainage holes at the bottom. Fill each container with good quality, well-draining potting soil. 

Overwintering

Columbines can withstand cold temperatures. At the end of their growing season, remove any wilted columbine foliage and cut columbine stalks to the ground. Flower stalks will regrow next spring, along with any new plants that successfully self-seeded. For extra protection from winter temperatures, scatter a light layer of mulch or decaying leaves around the plant crown.

Common Pests & Plant Diseases

Columbine foliage often bears the "doodling" of leaf miners, but the damage usually is not serious and gives the foliage a sort of randomly "variegated" look that can be appealing to some gardeners. Keep an eye out for the first signs of doodling, inspect the leaves for the larvae, and crush them with your fingers. You can also handpick leaves at the first sign of mining activity.

Other common pests include columbine sawflies and columbine aphids. Aphids can cause stunted growth while sawflies cause defoliation. To control aphids and sawflies, you can spray with ultra-fine horticultural oil or insecticidal soap.

Fungal diseases like gray mold and powdery mildew can affect columbine. Remove faded flowers to control gray mold from developing. If symptoms like a fuzzy gray mold or white mildew starts forming, apply a fungicide to control it.

How to Get Columbine to Bloom

Columbine plants bloom in mid-spring to early summer. Most columbine varieties have little to no scent, but Rocky Mountain columbine (Aquilegia caerulea) has a distinctive sweet smell. You can extend columbine's bloom period by pinching spent flowers back to just above a bud. If you do not deadhead spent blooms, the resulting seed production takes energy away from the plants. Columbine sown in spring will not bloom the first year; however, plants started in fall will bloom the following spring.

Common Problems With Columbine

Columbine plants can be grown in a range of climates and are easy to grow in a home garden. Like any garden plant, they are susceptible to a few problems, such as insect activity and fungal infections.

Yellowing Leaves

In areas with hot or dry summers, columbine leaves can turn yellow. If you keep the soil evenly moist, the plant might sustain itself. But if heat turns the leaves yellow or the plant dies down, cut the plant to its basal leaves. The plant is not dead. It might not come back until the next spring, but sometimes it can re-emerge in the early fall.

Leaves Turning White

Powdery mildew creates white powdery patches on the leaves. It can take over an entire plant, mainly during periods of high humidity when temperatures are warm and nights cool down. The fungus spreads through splashing water and travel by wind to infect other plants. Once established, powdery mildew is difficult to control. Treat an infected plant with a fungicide as soon as you notice symptoms; be sure to read instructions on the product label for proper application methods.

Leaves Disappearing

One day you can have a full columbine plant, and the next, the leaves are gone. This defoliation is a sign of a slug infestation. Slugs come out at night. Put out bait such as a pan of beer or an upside-down melon rind. The slugs will be attracted to both. They'll drown in the beer, and you can dispose of the slug-infested melon rind. You can also spread diatomaceous earth around the base of the plant. The slugs will not cross that barrier.