How to Grow Thornless Honeylocust 'Sunburst'

Thornless Honeylocust 'Sunburst'

Gleditsia triacanthos var. inermis 'Sunburst'

tree

Thornless Honeylocust 'Sunburst' is a deciduous ornamental tree prized for its bright golden-yellow foliage in spring that gradually matures to green in summer. This cultivar is thornless, making it safe for yards and parks, and features feathery, fern-like compound leaves that cast dappled shade. It grows to 40-50 feet tall with a vase-shaped crown and is valued for its fine texture and year-round visual interest.

Growing Conditions

☀️

Sun: Full sun, 6+ hours daily; tolerates partial shade but foliage color is best in full sun

💧

Water: Moderate water needs once established; drought-tolerant after the first 2-3 years. Water young trees deeply and regularly during the first growing season. Mature trees rarely need supplemental watering except during severe drought.

📏

Spacing: inches

📅

Days to maturity:

🌱

Planting depth: Plant at same depth as root ball; do not bury the base of the trunk

Soil

Type: Well-draining loamy to sandy soil; highly adaptable to poor, compacted, or alkaline soils

pH: 6.0-8.0

Amendments:

Compost at planting Sand or gravel if soil is heavy clay Mulch to retain moisture during establishment

Growing Zones

Find your zone →

Thrives in USDA zones 3b-9a; performs best in zones 5-8

3b 4a 4b 5a 5b 6a 6b 7a 7b 8a 8b 9a

Growth Stages

Bare Root/Container Dormancy

1-2 weeks before budbreak

Leafless branch structure visible; root system intact and ready for planting

Plant in early spring or fall; keep roots moist until planting; prune any broken branches

Spring Leafout & Golden Foliage

4-6 weeks (April-May in northern zones)

Bright golden-yellow compound leaves emerge; tree is full of light color, creating striking visual display

Establish regular watering schedule; monitor for pests; golden phase lasts 4-6 weeks

Summer Growth

12-14 weeks (June-August)

Foliage matures to soft green; tree develops full canopy and vase-shaped form; small greenish flowers appear in late spring/early summer

Reduce watering frequency if rainfall is adequate; prune lower branches if needed for clearance; fertilize young trees lightly

Fruiting & Fall Transition

8-10 weeks (September-November)

Flat, bean-like seed pods develop; foliage turns yellow-gold in fall before dropping; ornamental pod display persists into winter

Pods are not problematic but can create minor litter; appreciate the extended fall color and structural interest from pods

Winter Dormancy

12-16 weeks (December-March)

Bare branches with persistent seed pods visible; architectural form creates winter interest; tree is fully dormant

Prune only for structure and safety; remove dead or crossing branches; avoid heavy pruning

Companion Planting

Plan your garden →

Plant with:

Serviceberry (Amelanchier) Crabapple Redbud Flowering dogwood Viburnum Juniper Russian sage Black-eyed Susan Daylily

Avoid planting near:

Other honeylocust trees (to prevent cross-pollination and seedling proliferation) Water-loving plants sensitive to moderate drought Plants requiring acidic soil in very alkaline locations

Common Pests

Prune out webbed branches; apply BT (Bacillus thuringiensis) in mid-summer if severe; maintain tree vigor
Monitor for stippling on leaves; rarely requires treatment; use insecticidal soap if population is high
Prune damaged branches; apply neem oil in early season if needed; maintain good tree health
Increase humidity with water spray; use miticide only if severe; encourage natural predators
Prune out infected branches 12 inches below canker; sterilize tools; improve air circulation and avoid wounding bark

Uses

🌿

Ornamental Shade Tree

Landscape

Thornless Honeylocust 'Sunburst' is prized as a street tree and landscape specimen for its striking golden spring foliage, fern-like texture, and dappled shade that allows grass to grow underneath. Its vase-shaped form and variable height make it versatile for many landscape settings. [source]

🦋

Wildlife Habitat

Wildlife

The feathery foliage provides excellent nesting habitat for birds, and insects attracted to the tree support populations of songbirds and beneficial predators. The seed pods contribute to wildlife food sources, though they are not a primary food source for most wildlife. [source]

🏠

Dappled Shade & Energy Efficiency

Household

The open, lacy canopy of 'Sunburst' casts moving, dappled shade that reduces cooling costs for nearby buildings while allowing winter sunlight penetration. Planting on the west or south side of a house can reduce summer cooling needs by 20-30%. [source]

🎨

Winter Seed Pod Interest

Craft

The ornamental flat seed pods persist well into winter and can be collected and dried for floral arrangements, wreaths, or other craft projects, providing extended visual and textural interest. [source]

🍳

Edible Seed Pods

Culinary

The seed pods of honeylocust contain sweet, edible pulp that can be eaten raw or made into a nutritious beverage or meal supplement. Historically, honeylocust was used by Native Americans and pioneers as a food source. [source]

Harvest Tips

Not applicable; this is an ornamental tree. Seed pods may be collected in fall for propagation or composting if desired.

Fun Facts

🌱 The 'Sunburst' cultivar's golden spring foliage is a natural mutation that was selected and propagated for its ornamental value; the color results from the delayed production of chlorophyll as leaves emerge.
🌱 Thornless Honeylocust 'Sunburst' was developed to address the hazard of the native species' long, branched thorns—which can grow up to 8 inches long—making it much safer for yards and parks.
🌱 The common name 'honeylocust' refers to the sweet, honey-like flavor of the seed pod pulp, which can contain up to 40% sugar content in some trees.

Want personalized planting timelines?

Get started free