Is Ornamental Cabbage Perennial? Exploring the Lifespan of Flowering Kale
Ornamental cabbage, also known as flowering kale, is typically considered an annual or biennial plant, meaning it completes its life cycle in one or two years. While technically capable of surviving beyond two years under ideal conditions, its decorative appeal diminishes significantly, leading most gardeners to treat it as an annual.
Understanding Ornamental Cabbage and Kale
Ornamental cabbage and kale, Brassica oleracea, are cool-season vegetables prized for their vibrant foliage rather than their taste. They are closely related to edible cabbage and kale, but selective breeding has emphasized their leaf colors and textures. Often planted in the fall for winter interest or early spring before the heat arrives, these plants offer a splash of color when other garden elements may be dormant.
The Annual/Biennial Nature of Brassica oleracea
Most ornamental cabbage and kale varieties are marketed and used as annuals or biennials. Here’s why:
- First Year: The plant focuses on vegetative growth, developing its rosette of colorful leaves.
- Second Year (if Biennial): If it survives the winter, it will bolt, sending up a flower stalk, producing flowers, and eventually setting seed. The colorful rosette will fade and become less attractive.
- Beyond the Second Year: While technically the plant could persist beyond the second year, it will likely be unattractive, weak, and more susceptible to pests and diseases. Its ornamental value is essentially lost.
Therefore, even though Brassica oleracea may possess the biological capability to be a short-lived perennial under specific conditions, its horticultural lifespan is generally confined to one or two growing seasons.
Factors Affecting Ornamental Cabbage Lifespan
Several factors influence how long ornamental cabbage survives:
- Climate: Colder climates often result in the plant dying over the winter. Milder climates may allow it to survive, but the plant will bolt in the spring.
- Variety: Some varieties are more cold-hardy than others and may be more likely to survive the winter.
- Soil: Well-drained soil is crucial for preventing root rot, which can shorten the plant’s lifespan.
- Pest and Disease Control: Aphids, cabbage worms, and other pests can weaken the plant and reduce its chances of survival. Similarly, diseases like black rot can be fatal.
Extending the Ornamental Value (with Caveats)
While not truly perennial, you can take steps to potentially prolong the plant’s life, although its ornamental quality will still decline after the first year:
- Protection: Cover the plant during extremely cold weather to protect it from frost damage.
- Fertilization: Lightly fertilize in early spring to encourage new growth.
- Pest Control: Regularly inspect the plant for pests and diseases and take appropriate action.
- Deadheading: Remove spent flower stalks to prevent the plant from focusing its energy on seed production. This might delay bolting, but it will not prevent it entirely.
Comparing Annual, Biennial, and Perennial Plants
| Feature | Annual Plants | Biennial Plants | Perennial Plants |
|---|---|---|---|
| Lifespan | One growing season | Two growing seasons | Three or more growing seasons |
| Reproduction | From seed to seed in one season | Vegetative growth in year one, seed production in year two | Regrow from roots each year, often flowering annually |
| Examples | Marigolds, Zinnias, Impatiens | Carrots, Beets, Ornamental Cabbage/Kale | Hostas, Daylilies, Lavender |
FAQs: Ornamental Cabbage Deep Dive
Is it worth trying to overwinter ornamental cabbage?
While technically possible in milder climates, the ornamental value significantly decreases after the first year. The plant will bolt, become leggy, and lose its vibrant colors. It’s generally more rewarding to replant with fresh, young plants each year.
What should I do with my ornamental cabbage after it flowers?
After flowering, the plant has completed its life cycle. While you can let it go to seed, the plant will become unattractive and may attract pests. It’s generally best to remove the plant and compost it.
Can I propagate ornamental cabbage from cuttings?
Ornamental cabbage is typically propagated from seed, not cuttings. Cuttings may root, but the resulting plants are often weak and less vigorous.
What are the best conditions for growing ornamental cabbage?
Ornamental cabbage thrives in cool weather, well-drained soil, and full sun to partial shade. Plant them in the fall for winter color or in early spring before the summer heat arrives.
How often should I water ornamental cabbage?
Water regularly, especially during dry periods. Aim for consistent moisture but avoid overwatering, which can lead to root rot.
What are common pests and diseases that affect ornamental cabbage?
Common pests include aphids, cabbage worms, and slugs. Diseases include black rot and downy mildew. Regularly inspect your plants and take appropriate action to control these problems.
Can I eat ornamental cabbage?
While technically edible, ornamental cabbage is bred for its appearance, not its taste. It tends to be more bitter and less palatable than edible kale or cabbage.
Is ornamental cabbage deer-resistant?
Ornamental cabbage is not particularly deer-resistant. Deer may graze on the leaves, especially during the winter when other food sources are scarce.
What is the best time to plant ornamental cabbage?
Plant ornamental cabbage in the fall or early spring for the best results. Avoid planting during the hot summer months.
How much sun does ornamental cabbage need?
Ornamental cabbage prefers full sun to partial shade. In hotter climates, provide some afternoon shade to prevent the leaves from scorching.
Will ornamental cabbage reseed itself?
Yes, ornamental cabbage can reseed itself, but the resulting plants may not be true to type and may not have the same vibrant colors as the parent plant.
How do I choose the best ornamental cabbage varieties?
Choose varieties based on your climate and desired color and texture. Consider the maturity date to ensure the plants will be colorful when you want them to be.