How to Grow Red Salvia

red salvia

The Spruce / Letícia Almeida

In This Article

Native to Brazil, stunning red salvia flowers form a striking accent when massed together as bedding plants or lined up in a row as edging plants. They are also popular in container gardens, where they can serve as a vertical accent. This long-time garden favorite will serve as a great addition to your yard in the summer and early fall if you follow a few simple rules about location and plant care.

Plant taxonomy classifies red salvia plants as Salvia splendens. Despite an official common name of scarlet sage, many people refer to the plants simply as red salvia. They are members of the mint family and, while technically a perennial plant, red salvia is often grown as an annual in temperate zones. Although the scarlet variety is the best known, Salvia splendens comes in other colors including white, salmon, pink, purple, lavender, burgundy, and orange.

Best planted in mid-spring once the soil has warmed to at least 70 degrees Fahrenheit, red salvia will grow quickly, eventually reaching heights of 18 to 30 inches at maturity. The dark-green, heart-shaped leaves emit a fragrance that mammalian pests dislike, making them both deer and rabbit resistant.

Botanical Name Salvia splendens 
Common Name  Red salvia, scarlet sage, blood sage
Plant Type  Herbaceous perennial
Mature Size  1–2 feet tall, 9–18 inches wide
Sun Exposure  Full sun to partial shade
Soil Type Moist but well-drained 
Soil pH Neutral to acidic
Bloom Time Summer into fall
Flower Color Red
Hardiness Zones 10–11 (USDA)
Native Area Brazil
Toxicity Non-toxic
closeup of red salvia
The Spruce / Letícia Almeida
red salvia
The Spruce / Letícia Almeida
red salvia in a landscape
The Spruce / Letícia Almeida
red salvia
The Spruce / Letícia Almeida 

Red Salvia Care

If you're looking for a plant to add vibrant color to your garden—without requiring a lot of care—red salvia might be the plant for you. To thrive, red salvia needs enough sunlight and well-draining soil. Beyond that, you will barely have to think of this eye-catching specimen, except when guests inevitably ask what that cool plant is.

To improve the look of your red salvia (and to encourage them to produce bountiful flowers), it's important to deadhead faded blooms. You can do this by pinching off the flower spikes that have finished blooming—make sure to pinch down to the bottom of the stems.

Light

Red salvia can grow successfully in a spot that receives partial shade, but ultimately it will grow (and bloom) better the more hours of sun it receives. Strive to plant your salvia in a location that gets at least six to eight hours of bright sunlight per day.

Soil

Plant your red salvia in soil that is moist but well-draining. The plant prefers a loamy mixture that is rich in organic matter but doesn't get boggy or retain too much water. If the soil in your landscape isn't nutrient-dense, amend it with organic matter before planting. Mulching the top layer of the soil can also help a sandy mixture retain a bit more moisture, especially during the hotter summer months.

Water

Red salvia plants like consistently moist soil, but overwatering them can cause roots to rot. Generally, a watering schedule of every seven to ten days is sufficient, depending on rainfall amounts and hot daytime temperatures. Before watering, verify that the first inch or two of soil is dry. If soil is dry, water deeply to ensure water reaches the plant roots.

Temperature and Humidity

Red salvia plants are fairly temperature-sensitive and prefer to be grown in soil (and environmental) temperatures that are consistent. Most importantly, red salvia is not frost tolerant and should not be subjected to prolonged temperatures below 32 degrees Fahrenheit. Red salvia does not have any special humidity needs.

Fertilizer

For best results, fertilize red salvia plants with the same balanced fertilizer you use to fertilize your other annual flowering plants. Generally, red salvia plants are not heavy feeders and will do fine with just one springtime fertilization.

Other Salvia Varieties

Many cultivars of salvia sold at garden centers and online. While they all have the same care requirements, they will often vary in both color and height. Some of the most popular varieties include:

  • 'Alba': a variety with white flower spikes that can grow to 24 inches tall
  • 'Ablazin™ Purple' a variety that produces royal purple flower spikes and can reach 26 inches tall
  • 'Carabiniere': a compact variety with red flower spikes that grows to 14 inches tall
  • 'Salsa Scarlet Bicolor': a unique variety that features bicolored red and white flower spikes and reaches a height of just 6 to 12 inches tall

Common Pests/Diseases

Monitor red salvia for pests like slugs, snails, and whitefly, all of which might bother the plants. In fact, when shopping for plants at the garden center, carefully inspect the undersides of the leaves for whitefly to avoid bringing any home with you. Whiteflies are notorious greenhouse pests, and, occasionally, they will make the trip from the greenhouse to the garden center, undiscovered.

If a plant is infected, remove the pests with a strong blast of water (from a garden hose). If that doesn't work, treat the plant with a mild insecticidal soap or horticultural oil like neem oil. Keep in mind, your applications will need to be repeated until all signs of infection have ceased.