This charming Mediterranean annual can't be passed up. Honeywort (Cerinthe major) features delicate, bell-shaped flowers surrounded by colorful bracts and framed by rounded green-gray foliage. While the flowers are fairly small and insignificant, it is the large, tubular bracts that are one of honeywort's most striking features. They outlast the small flowers and hold onto their beautiful color for several weeks. Depending on the species, honeywort can come in a variety of colors, though the blue and purple species are the most popular.
Honeywort is easy to grow in garden beds and containers, and it makes for a great cut flower. Plus, its nectar-rich flowers attract hummingbirds, butterflies, bees, and other pollinators. It has a fast growth rate and should be planted in the spring after the threat of frost has passed.
|Botanical Name||Cerinthe major|
|Common Names||Honeywort, blue shrimp plant|
|Mature Size||1–3 ft. tall, 1–2 ft. wide|
|Sun Exposure||Full, partial|
|Soil Type||Loamy, well-drained|
|Soil pH||Acidic, neutral (6.1–7.8)|
|Bloom Time||Summer, fall|
|Flower Color||Blue, purple, magenta, yellow, cream|
|Hardiness Zones||7–10 (USDA)|
How to Plant Honeywort
Honeywort produces large black seeds that fall to the ground in the late summer or early fall, which can be harvested for future growth. Many gardeners start their honeywort from seed, especially because nursery plants aren’t always easy to find. Start your seeds roughly four to six weeks before your area’s projected last frost date. Soak them in water overnight. Then, press them into a seed-starting mix about a quarter-inch deep, and keep the potting medium warm and moist. They should germinate within three weeks if the temperature remains between 65 and 85 degrees Fahrenheit.
Once seedlings are a few inches high and the weather is reliably warm, bring your plants outside for progressively longer stretches. After about a week of this, they are ready to plant in the garden. Space each plant around 12 to 18 inches apart.
For the most vibrant colors, honeywort needs at least five to six hours of full sun per day. It also can tolerate a bit of shade. But too much shade can cause honeywort to become leggy, and its colors will be less bright.
Honeywort prefers an organically rich, loamy soil with good drainage. The soil should still retain a decent amount of moisture as honeywort does enjoy moist conditions, but it should not become waterlogged. A slightly acidic to neutral soil pH is best.
For optimal flower production, water honeywort regularly throughout the growing season. A good rule is to water whenever the soil feels dry one to two inches down. Once the plant is established it will have some drought tolerance, but flower production will suffer without adequate water.
Temperature and Humidity
This flowering annual thrives in temperatures between 65 and 75 degrees Fahrenheit and moderate humidity levels, but it can tolerate warmer and cooler temperatures as well. However, it is not hardy to frost. In regions with cold winters, the plants might not self-seed as easily as they do in warmer areas.
When grown in appropriate soil, honeywort does not require any fertilization. However, amending the soil with some compost or manure to keep it rich in organic matter will help to support healthy growth. When grown in containers, honeywort can benefit from monthly fertilization with an all-purpose fertilizer.
The Cerinthe genus contains multiple species and cultivars, including these varieties:
- Cerinthe major 'Purpurascens' is one of the most popular cultivars of honeywort and is characterized by intense purple flowers with bracts and sepals in varying shades of blue-violet.
- Cerinthe major 'Kiwi Blue' is harder to find commercially and is characterized by bluer bracts and flowers than the 'Purpurascens' cultivar.
- Cerinthe major 'Purple Belle' has brilliant magenta flowers and grows only 2 feet tall.
- Cerinthe minor is a smaller, yellow-flowered species and is considered to be a perennial hardy to zone 5.
- Cerinthe retorta is characterized by pale yellow flowers with blue-purple tips, encased by dark purple bracts.
Honeywort is commonly harvested for use as a cut flower. When the bracts darken, they are at their peak color to harvest. Do so in the coolest part of the day, so the stems are still plump with moisture. Trim the stems with sterile shears, and place your cut flowers in cool water. The flowers should last roughly seven to 10 days.
Moreover, you can harvest seeds to propagate future plants. You can either gather seeds as they fall naturally from the plants in the late summer and fall. Or cut blooming stems and bring them inside to dry and release their seeds inside a bag. Store seeds in an envelope in a cool, dry place until you're ready to start them the next spring.
How to Grow Honeywort in Pots
Honeywort grows well in containers, but its care must be adjusted slightly. Choose a container that has ample drainage holes to prevent root rot, and use a quality all-purpose potting mix that's loose and drains well. If your pot has a saucer, always empty it promptly if it fills with water. When grown in containers, honeywort typically requires more frequent watering than when it's grown in the ground, especially during hot weather. Use an all-purpose liquid plant food on the container from spring to early fall, following label instructions.
Honeywort. University of Wisconsin Horticulture Extension Division