7 Tropical Bulbs for a Summer Garden That Wows

Traditional spring bulbs wither in summer heat, but subtropical bulbs shine. They add bold, dramatic colors and patterns anywhere. In temperate regions, dig them up in fall and replant in spring; in warmer climates, they're returning perennials. They're also great replacements for gardeners in warm zones who can't grow typical spring bulbs like crocus or daffodil. Most are technically corms, rhizomes, or tubers, but grouped as bulbs for simplicity.

Warning: Flowering bulbs may be toxic if consumed. See more plant cautions for pet owners

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Elephant Ear (Alocasia, Colocasia spp.)

For a lush tropical look, grow these large-leaved arum relatives — think caladiums on steroids. 'Borneo Giant' (Alocasia 'Borneo Giant', zones 9–11) reaches 12 feet. More modest varieties offer eye-popping colors: 'Mojito' (Colocasia 'Mojito', zones 7–11) with lime-green dappled leaves, 'Black Magic' (Colocasia 'Black Magic', zones 7–11) with near-black foliage.

• USDA zones: 7–11
• Water & soil: Tolerates drought and standing water; thrives in rich, moist soil
• Light: Full shade to full sun
• Mature size: 2–12 feet tall
• Bloom time: Spring through summer
• Planting tips: Give plenty of space. In the Southeast, avoid planting elephant ear from drainage ditches — likely invasive Colocasia aquatica.

Gingers (Alpinia, Hedychium, Curcuma etc.)

Exotic blooms and quintessentially tropical foliage. Plant variegated shell ginger (Alpinia zerumbet 'Variegata') for gold-and-green pinstriped leaves and shell-like blooms where it rarely freezes. For quick gratification, Curcuma gingers like Siam tulips (Curcuma alismatifolia, zones 8–11) bloom 1–2 months after leaves appear. Turmeric (Curcuma longa, zones 7b–11) offers edible, nutritious roots. Butterfly ginger (Hedychium coronarium, zones 7b–11) has sweet, spicy gardenia-like fragrance.

• USDA zones: 7b–11
• Water & soil: Rich, well-drained soil with ample moisture
• Light: Full to partial shade
• Mature size: Usually ≤5 feet tall
• Bloom time: Varies, usually summer
• Planting tips: In zones 9–11, reduce winter watering for dormancy.

Crinums (Crinum spp.)

Old saying: you can't kill a crinum. Established clumps in old gardens live decades. Hardy crinum (Crinum bulbispermum, zones 5–11) has pink flowers and twisted gray-green foliage. 'Ellen Bosanquet' (Crinum 'Ellen Bosanquet', zones 6b–11) is a Southern favorite with fragrant pink blooms. Grand crinum (Crinum asiaticum, zones 9–11) reaches 6 feet with spidery white flowers.

• USDA zones: 6–11
• Water & soil: Tolerates wide range
• Light: Full shade to full sun
• Mature size: 1–6 feet tall
• Bloom time: Varies
• Planting tips: Killing a crinum is harder than keeping one alive; they look best with old leaves removed.

Derviss Design

Canna (Canna spp.)

Quickly add height in mere months — ideal for temperate climates with shorter summers. Plant en masse at back of beds or as thrillers in containers. In modern designs, minimalist upright leaves fit right in. 'Phaison' (aka Tropicanna, zones 7b–11) has intensely striped purple, orange, deep green leaves. 'Australia' (zones 7b–10) has jet-black leaves and burning-red flowers.

• USDA zones: 7–11
• Water & soil: Best with rich, well-drained soil and regular water; many tolerate standing water
• Light: Partial to full sun
• Mature size: 1–10 feet tall (many heights available)
• Bloom time: Summer through fall
• Planting tips: Avoid virused plants (streaked/pale foliage). Rolled leaves = canna leaf roller; cut affected stems to ground.

Other Tropical Bulbs

The above have major presence, but for something more down-to-earth, try these smaller standouts:

• Blood lily (Haemanthus multiflorus, zones 8b–11): Grapefruit-size fireworks in June on leafless stalks — magical.
• Rain lilies (Zephyranthes, Habranthus spp., zones 7–11): Sporadic blooms year-round with trumpet flowers in white, yellow, pink.
• Caladiums (Caladium bicolor, zones 9b–11): Popular for harlequin vein patterns in pink, green, red, white. Gouge growing point of corms after digging for more blooms.

Peter Raarup Landscape Design

Designing with Tropical Bulbs

Don't hesitate to plant multiples — these plants don't skimp on impact. A single caladium evokes whimsy; three together become a focal point. Since they multiply, a single plant looks unnatural. They look best surrounded by finely textured plants.

www.KarlGercens.com

Temperate Climates

Anyone can grow tropical bulbs, even for a few months. Plant with spring bulbs once days warm; they'll continue until frost. Grow in containers for a head start indoors in winter, bring back indoors when nights get frosty. Water sparingly through winter or rinse soil and store, replanting in early spring. Plants with less-developed roots (African irises, heliconias) are good candidates.

Digging and storing: Wait until first frost kills leaves, lift carefully, rinse soil, dry in dark place, store in shredded newspaper, vermiculite, or sawdust (shoe boxes, plastic containers, paper bags work). Spray with fungicide if desired, keep cool and dark until spring, check periodically, remove rotted portions.

Raymond Jungles, Inc.

Hot Climates

Nothing compares to tulips or crocuses in snow, but tropical bulbs offer their own magic. Massed blue agapanthus or pink caladiums are stunning; fleeting rain lilies, blood lilies, hurricane lilies rival snowdrops.

If hardy in your region, grow them permanently in ground: they bounce back from drought, damage, weed trimmers — clumps of crinums outlive original homes. They form impressive clumps, become garden assets, and make great pass-along plants.