How to Grow Cornflower
Easy to start from seed, this annual plant is hugely popular as a bedding plant or cut flower for home gardeners and florists, prized for their brilliant blue flowers, reminiscent of wild chicory. Cornflower is a member of the Asteracea or Compositae family, which is a large and widespread group of plants that includes sunflowers, daisies, and asters.
The soft, frilly double blossoms with fringed petals and delicate gray-green feather foliage make them an excellent cut flower, complemented by zinnias, calendula and other brightly colored cutting garden blossoms.
Starter plants for Cornflowers are available in most garden centers, yet often lack the diversity of colors, making this a good reason to start from seeds.
Coneflowers are often used as a boutonniere in weddings, and because of their popularity, have been bred to produce plants for a wider range of blossom colors, which included white, pink, red purple, deep burgundy (sometimes called black) and the crisp blue which is the only true natural color.
When & Where to Plant Cornflower
Light: Full sun, open fields.
Soil: Moist, well-drained soil. Can tolerate drought conditions, once established.
Spacing: Allow 8-12 inches in between plants.
Planting: Sow seeds in early spring for summer blooming plants. In more moderate climates, seeds can be sown in early fall, and established plants will bloom the following spring and summer.
How to Grow Cornflower Throughout the Season
Growth Habit: Cornflowers vary in size, depending on the variety. Shorter types are best in the front of the border, while taller varieties are best mid-garden. Plants tend to grow upright, rather than spread, yet the more blossoms are cut, the more buds they will produce and the plants will get bushy and full.
Staking: No staking is required, unless grown in a greenhouse for cut flower trade.
Watering: Cornflowers are generally tolerant of drought conditions, yet thrive when watered frequently.
Fertilizing: In early spring, work fertilizer into the soil. Side dress in mid-summer with a well-balanced fertilizer, or one with higher phosphorous to boost flower production.
Mulching: Cornflowers benefit from mulching with bark mulch, to protect from drying out and too much sun to the root system.
Cornflower: End of Season Care
Cornflowers are annuals, and at the end of the season remove plants, along with the roots, and place on the compost pile.
Dividing & Transplanting: Annual Cornflower ( C. Cyanus)require no dividing, yet can be transplanted as young seedlings into the garden where they are to grow for the season.
Pests & Disease: Cornflowers are relatively carefree, yet can be susceptible to stem rot and rust, if grown too tightly in a bed with not enough air in-between to circulate. Garden pests that can affect Cornflowers include aphids and leafhoppers, which will weaken the stems, causing the plant to expire.
Additional Concerns: Like most annual flowers, remove spent blossoms to encourage vigorous growth, and to keep a continuum of showy blossoms all season.
Cornflower: Extra Info
Companion Plants: In the garden, they are visually stunning planted with brightly colored Nasturtiums, Marigold and California Poppies. In a vase, they blend well with Snapdragons, Sweet William and Love-in-a-Mist or Nigella.
Additional Uses: Cornflowers have been used as a natural plant dye, and are edible and can used as a garnish for the plate.
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