Sunburst honeylocust

Sun

Full sun gives the strongest yellow foliage; tolerates light partial shade.

Water

Water deeply during establishment. Once established, it tolerates dry spells, but prolonged drought can cause early leaf drop.

Soil

Adaptable to clay, loam and sandy soils, including alkaline soil, provided drainage is reasonable. Avoid persistently waterlogged ground.

Height

30-40 ft (9-12 m)

Spread

20-35 ft (6-11 m)

Foliage

Fine-textured, divided leaves emerge golden yellow, mature to pale green and turn yellow in autumn. Fresh shoot tips can remain yellow against the older green foliage.

Growth

Moderate to fast, particularly while young.

Care needed

Medium

• Deer resistant
• Drought tolerant
• Cold hardy
• Wildlife

Northern hemisphere months. In Australia, shift them by six.

Difficulty

Moderate

Toughness

Very tough

Pick your zone, country, light and whether you have pets.

1. Planting day

   7 ft (2 m)

2. After 1 year

   8 ft (2.5 m)

3. After 2 years

   10 ft (3.1 m)

4. After 3 years

   12 ft (3.6 m)

5. After 5 years

   15 ft (4.7 m)

About 16 years to full size.

From a typical nursery size, at an average rate for this kind of plant. A rule of thumb, not a forecast.

Cats and dogs

Safe

Native to

the US and Canada

Invasive in

Australia

Growth rate

Fast

• Water deeply through the first two growing seasons whenever the root zone begins to dry.
• Spread mulch 2-3 in (5-8 cm) deep over the root area, keeping it clear of the trunk.
• Stake only if the root ball moves in the wind; remove supports after the first growing season if the tree is stable.
• Avoid routine feeding on reasonably fertile soil; excessive nitrogen encourages weak, soft growth.
• Remove shoots arising below the graft union, especially any bearing thorns.

Pruning. Train a young tree in late winter to maintain one main leader and well-spaced branches; remove competing leaders and damaged or crossing growth. Keep pruning cuts small and use a qualified arborist for large branches.

Late winter

Check the branch structure and lightly prune young trees before growth begins.

Spring

Plant when the soil is workable and not waterlogged; water thoroughly and mulch.

Late spring

Inspect unfolding leaves for distorted growth, webbing or honeylocust plant bug damage.

Summer

Water young trees deeply during dry weather and check for mites if leaves look stippled or bronze.

Early autumn

Check stakes and ties, removing supports that are no longer needed.

Late autumn

Top up mulch without covering the trunk flare, and remove any thorny rootstock suckers.

• Use as a lawn specimen where the yellow spring canopy can be seen against darker trees.
• Provide light shade beside a terrace without creating the dense canopy of many larger shade trees.
• Underplant with shade-tolerant perennials and spring bulbs for a layered garden.
• Pair with dark green or purple foliage to make the golden new growth stand out.

Garden styles it suits: Modern, Mid-century modern, Traditional, Grand estate, Autumn colour and Family-friendly.

Plant it with: Hellebores, Epimediums, Japanese forest grass, Hardy geraniums, Daffodils and Coral bells.

Wildlife: The canopy provides perches and cover for birds, and the foliage supports some insects. This largely podless cultivar offers little of the seed food produced by ordinary honeylocust.

• Honeylocust plant bugs can distort and brown young leaves. Established trees usually recover without treatment; maintain adequate water and avoid unnecessary spraying.
• Spider mites cause fine stippling, bronzing and premature leaf fall in hot, dry weather. Water during drought and rinse reachable foliage; avoid broad-spectrum insecticides that kill mite predators.
• Mimosa webworm ties leaflets together with silk and causes brown patches. Remove small accessible webs promptly; seek local advice if repeated defoliation becomes severe.
• Cankers and branch dieback are more likely on stressed or injured trees. Protect the trunk from mower damage, water during drought and have affected branches assessed and removed.

Honeylocust is not known to be toxic to cats, dogs, horses or people. Leaves and pods are not generally considered poisonous, but do not confuse it with toxic black locust. Thorny rootstock shoots can cause puncture injuries.

Where it spreads. The species spreads aggressively in parts of Australia, particularly Queensland and New South Wales, where legal controls apply in some jurisdictions. Sunburst is largely podless and has much lower seed-spread potential, but check local restrictions before planting; rootstock shoots may be thorny and capable of producing pods.

• Golden black locust (Robinia pseudoacacia 'Frisia')

  Has larger oval leaflets, often paired prickles at the leaf bases, and sometimes hanging clusters of white pea-like flowers. Its foliage usually stays yellow longer, and black locust is toxic.

• Ordinary honeylocust (Gleditsia triacanthos)

  Usually has green rather than golden new foliage; seed-grown trees may carry large branched thorns and long, flat brown pods.

• Golden Japanese pagoda tree (Styphnolobium japonicum 'Princeton Upright')

  Has broader leaflets and lacks honeylocust's finely divided appearance. Its flowers are creamy pea-like blooms, and its pods are constricted between the seeds.

Gleditsia honours the German botanist Johann Gottlieb Gleditsch, triacanthos means three-spined, and Sunburst refers to the cultivar's golden young foliage.

Propagation. Usually propagated commercially by budding or grafting onto honeylocust rootstock. Seed does not reproduce Sunburst faithfully; buy a correctly labelled grafted tree.

Accepted botanical name

Gleditsia triacanthos

In the US and Canada

Native in Canada and the lower 48 states.

Native range

Alabama, Arkansas, Connecticut, Delaware, Florida, Georgia, Illinois, Indiana, Iowa, Kansas, Kentucky and Louisiana.

Measured

Soil pH 4.8 to 8. Average height 1675 cm.

Sources: GBIF (CC BY 4.0), USDA PLANTS and Trefle (CC BY 4.0). The care and design notes are LandscapeGPT's own.