Annual
Scarlet Sage / Annual Salvia
Salvia splendens · Lamiaceae (mint family)
Also called: Scarlet Salvia, Red Salvia, Tropical Sage
Scarlet Sage / Annual Salvia (Salvia splendens) is a moderate-water annual well suited to Tucson and the low desert. It thrives in full sun, with a fast growth rate.
Scarlet Sage / Annual Salvia at a glance
- Water use
- Moderate (established)
- Sun
- Full sun; in Tucson, full morning sun with light afternoon shade in peak summer keeps it from scorching.
- Mature size
- 10-24 in tall, 9-15 in wide (dwarf bedding strains are most common).
- Growth rate
- Fast
- Bloom
- Scarlet red (also available in white, salmon, purple, burgundy strains)., Spring through summer/fall in Tucson; blooms heaviest in spring and again as heat eases in fall.
- Cold hardiness
- Frost-sensitive; damaged/killed at/below 32F. Treated as a warm-season annual in USDA 9a-9b. Replace each year.
- Soil
- Loose, fertile, well-drained soil amended with organic matter; tolerates a range of pH but dislikes heavy, poorly drained clay.
- Native range
- Brazil (South America)
- Best used as
- Mass color bedding, Borders and flower beds, Containers and patio pots, Pollinator/hummingbird gardens
- Wildlife
- Tubular scarlet flowers strongly attract hummingbirds and butterflies; not browsed by rabbits as readily as many annuals.
- Toxicity
- Generally considered non-toxic / low risk to dogs, cats, and children (not a listed toxic plant); ingestion may cause mild stomach upset.
How to grow Scarlet Sage / Annual Salvia in Tucson & the low desert
Watering
Warm-season bedding annual for Tucson: set out transplants after the last frost (mid-March to April) for spring-into-summer color; one of the more heat-tolerant annual salvias. Keep soil consistently moist but not waterlogged, deep-watering 2-3x/week in spring and daily during 100F+ stretches in containers.
Fertilizer & nutrients
Feed every 2-4 weeks with a balanced or bloom-type (higher-phosphorus) water-soluble fertilizer to sustain continuous spike production; amend native soil with compost at planting.
Pruning & care
Deadhead/shear spent flower spikes regularly to force rebloom and prevent a tired, leggy look; pinch young plants once to encourage branching.
Notes
In the low desert, plant in spring for the best show; it handles Tucson heat better than petunias but appreciates afternoon shade and steady moisture once temperatures exceed 100F. Often re-set in fall for a second flush.
Sources: University of Arizona Cooperative Extension - Pima County Monthly Gardening Guides (extension.arizona.edu); Pima County Master Gardeners; Clemson HGIC Salvia factsheet (hgic.clemson.edu)