Can Calla Lilies Be Planted Outside? Expert Guide

By David Wilson · May 30, 2025

Yes, calla lilies can be planted outside in USDA hardiness zones 8–10, where they thrive as perennials. In colder zones (7 and below), they can be grown outdoors as summer annuals or lifted and stored over winter. Proper sunlight, well-drained soil, and consistent moisture are key for healthy growth and blooming.

Understanding Calla Lilies: Outdoor Growing Basics

Calla lilies (Zantedeschia spp.) are prized for their elegant, funnel-shaped blooms and lush foliage. While often associated with indoor containers, they perform exceptionally well when planted outdoors under the right conditions. Their adaptability makes them a favorite among gardeners seeking both ornamental beauty and low maintenance appeal.

Key Factors for Successful Outdoor Planting

Climate Zone Compatibility: Calla lilies grow best in warm climates (zones 8–10) but can be seasonally planted in cooler regions.
Sunlight Requirements: Prefer full sun to partial shade (6–8 hours of light daily).
Soil Conditions: Require moist, well-drained soil rich in organic matter; avoid waterlogged areas.
Frost Sensitivity: Tubers are not frost-tolerant and must be protected or dug up in cold winters.
Blooming Period: Typically flower from late spring through summer, depending on planting time and climate.

Best Time to Plant Calla Lilies Outdoors

The optimal planting window is after the last frost date in spring when soil temperatures reach at least 55°F (13°C). In zone 8 and above, fall planting allows tubers to establish before winter dormancy. Gardeners in zones 4–7 should plant in mid-spring for summer performance.

Regional Planting Guidelines

USDA Zone	Last Frost Date	Recommended Planting Time	Lifespan (Outdoor)
4–6	April–May	Mid-May	Annual (lift before frost)
7	March–April	April	Short-lived perennial (with mulch)
8–10	January–March	October–March	Perennial
11+	Frost-free	Year-round	Evergreen perennial

Table data source:USDA Plant Hardiness Zone Map, Texas A&M AgriLife Extension

This data shows that planting timing and longevity of calla lilies are closely tied to regional climate resilience. In warmer zones (8–11), callas survive year-round with minimal care, while colder zones require seasonal management. The transition zone (7) offers marginal success with protective measures like heavy mulching.

Care Tips for Outdoor Calla Lilies

To ensure vibrant blooms and strong foliage, follow these proven care practices:

Watering Needs

Keep soil consistently moist but not soggy. Calla lilies naturally grow in wetlands, so they tolerate more water than many bulbs, but prolonged standing water encourages rot.

Fertilization Schedule

Apply a balanced fertilizer (10-10-10 NPK) every 4–6 weeks during active growth. Reduce feeding once flowering begins to prevent excessive leaf production.

Pest and Disease Management

Aphids & Spider Mites: Treat with insecticidal soap or neem oil.
Rhizome Rot: Caused by poor drainage; improve soil structure with compost or raised beds.
Botrytis Blight: Occurs in humid conditions; ensure good air circulation between plants.

Overwintering Calla Lilies in Cold Climates

In zones 7 and below, it's essential to lift and store tubers before the first hard frost:

Dig up tubers after foliage yellows (usually fall).
Clean off excess soil and allow to dry for 1–2 weeks in a cool, shaded area.
Store in peat moss or vermiculite in a dark place at 50–60°F (10–15°C).
Replant in spring after frost danger passes.

Alternatively, grow calla lilies in containers and move indoors before freezing temperatures arrive.

Frequently Asked Questions About Planting Calla Lilies Outside

Can calla lilies survive winter outdoors?

Yes, but only in USDA zones 8–11. In these regions, calla lily tubers remain in the ground year-round with a layer of mulch for insulation. In colder zones, tubers must be dug up and stored indoors to prevent freezing damage.

Do calla lilies prefer sun or shade when planted outside?

They perform best in full sun (6–8 hours daily) but benefit from afternoon shade in hot climates (zones 9–10). Too much shade leads to leggy growth and fewer flowers.

How deep should I plant calla lily rhizomes outside?

Plant rhizomes 2–4 inches deep with the eyes facing upward. Space them 12–18 inches apart to allow room for spreading. Deeper planting may delay emergence but protects in marginally cold zones.

Are calla lilies deer resistant?

Yes, calla lilies are generally deer and rabbit resistant due to their slightly toxic sap. This makes them an excellent choice for gardens prone to browsing wildlife.

Can I leave calla lilies in pots outside all year?

You can in zones 8–11, provided pots are insulated and not exposed to prolonged freezing. In colder zones, move potted callas to a garage or basement after cutting back foliage to protect the rhizomes.