Red salvia (Salvia splendens) is a popular garden plant grown for its bright red flower spikes. Many gardeners wonder whether red salvia is an annual or a perennial. The answer is that red salvia is generally grown as an annual, but in some climates it may survive the winter and come back year after year as a short-lived perennial.
Annual vs. Perennial Plants
Annual plants complete their entire life cycle in one growing season. They germinate from seed, grow, flower, set new seed, and die all within a single year. Annuals must be replanted each year from seed or new plants. Examples of popular annual flowers include zinnias, marigolds, petunias, and many types of salvia.
Perennial plants live for multiple years. They germinate and grow the first year, overwinter, then return to grow and bloom again the next year. Perennials continue this cycle for many years before dying. Examples of perennial garden flowers include peonies, coneflowers, and daylilies.
Red Salvia’s Growth Habits
Red salvia is native to the highlands of Brazil, where it thrives in the mild, frost-free climate. When grown as an annual in colder climates, it produces abundant blooms throughout the warm months of summer. As fall approaches and temperatures drop, the plant dies after setting seed.
However, red salvia can sometimes overwinter successfully where winters are relatively mild. In warm coastal areas or in zones 8-10, established plants may survive through winter. The plants will likely die back to the ground after frost, but roots remain alive. New growth resumes in spring and flowers return.
Overwintering Tips
To improve the odds of red salvia overwintering, there are a few strategies to try:
- Choose a protected location, such as near the foundation of a building or wall.
- Apply a thick mulch around the base to insulate roots from cold.
- Prune plants by about one-third in fall so they require less energy to overwinter.
- Cover plants with a cold frame or fabric row cover as extra protection.
Even with the best care, there is no guarantee that red salvia will return reliably each spring. It depends on weather factors like extreme cold snaps. But in very favorable conditions, the plants may thrive for 2-3 years or longer before needing to be replaced.
Growing Red Salvia as an Annual
Whether or not red salvia survives the winter, most gardeners choose to replace their plants each spring and grow salvia as a fast and prolific annual flower.
Planting
Red salvia should be planted out in the garden after all danger of frost has passed. This is usually early to mid spring in most climates. Start seeds indoors 6-8 weeks before the last expected frost date.
Choose a site with full sun. Space plants 10-18 inches apart in well-drained soil. Add compost or fertilizer to poor soils to provide the nutrition these fast growers require.
Care
Red salvia grows quickly once established. It benefits from moderate watering when rainfall is lacking. Feed plants monthly with a balanced liquid fertilizer or work aged compost into the soil around plants.
Pinch back leggy growth to encourage bushiness. Remove spent flower spikes to promote continuous blooming into fall. By cutting back any faded blooms promptly, plants will produce new flowers until late in the season.
Overwintering as Houseplants
In climates where outdoor overwintering is not possible, some gardeners dig up a few red salvia plants each fall and grow them as houseplants through the winter. Cut back foliage by half before bringing indoors. Repot in a container just slightly larger than the root ball.
Place in a sunny window and water when the top inch of soil becomes dry. Fertilize monthly. The lower light levels indoors may inhibit flowering until the plants can be moved back outside the following spring.
Key Differences
Here is a table summarizing the key differences between growing red salvia as an annual versus as a perennial:
| Annual | Perennial |
|---|---|
| Must replant each year | May regrow for 2-3+ years |
| Not winter hardy | Has some winter hardiness |
| Fast and abundant bloomer | Flowers less freely |
| Full sun for best flowering | Can tolerate some shade |
Conclusion
While red salvia may survive winters and regrow as a short-lived perennial in ideal warm climates, most gardeners find it easier to simply replant each year for heavy flowering. Grown as an annual, red salvia is easy to start from seed, trouble-free, and provides bold color in flower beds and containers all season long.
In colder zones where it cannot reliably overwinter, dependable performance will require planting new red salvia each year. But the beauty of its dramatic red blooms and flower production make it well worth growing even as an annual. With proper planting and care, red salvia is sure to provide stunning color and visual interest to gardens and landscapes.
