How far apart should I plant Honey locust?

About 10 m (33 ft) apart, centre to centre. A mature plant spreads 10–15 m (33–49 ft).

Does Honey locust need full sun?

Full sun: at least 6 hours of direct sun a day.

How much water does Honey locust need?

Low water. Drought tolerance is high and waterlogging tolerance moderate.

How cold-hardy is Honey locust?

It tolerates about -34 °C (-29 °F) once established, roughly USDA zone 4.

When does Honey locust flower?

From about June for 1–3 weeks (northern hemisphere; later in cold climates, earlier in warm ones).

Is Honey locust poisonous to cats and dogs?

For cats it is not well documented; for dogs not well documented; for people mildly toxic. Thorns cause puncture wounds and unripe pods can upset the stomach; pet toxicity is not well documented.

What grows well with Honey locust?

"Three sisters": climbing beans use corn as a support and fix nitrogen; the benefit to the corn is modest but real in low-input soils.

Honey locust Gleditsia triacanthos

Honey locust (Gleditsia triacanthos) is a deciduous perennial tree in the Fabaceae family, native to Central and eastern North America. It grows 12–20 m (39–66 ft) tall and 10–15 m (33–49 ft) wide, wants full sun and low water, and is hardy to about -34 °C (-29 °F). Space plants about 10 m (33 ft) apart.

Plan Honey locust in your garden →
Free. Draw your beds, then watch it grow through the year in 2D and 3D.

Honey locust at a glance

Type	Perennial tree, deciduous
Family	Fabaceae
Mature height	12–20 m (39–66 ft)
Mature spread	10–15 m (33–49 ft)
Spacing	10 m (33 ft) centre to centre
Sun	Full sun, at least 6 h of direct sun a day
Water	Low; drought tolerance high, waterlogging tolerance moderate
Soil pH	5.5–8
Cold hardiness	About -34 °C (-29 °F) once established (roughly USDA zone 4)
Heat stress	Likely above about 40 °C (104 °F)
Flowering	from about June for 1–3 weeks (northern hemisphere; later in cold climates, earlier in warm ones)
Wind tolerance	Moderate
Pollinator value	Moderate
Edible	Yes: pod pulp (sweet, small amounts)
Native to	Central and eastern North America
Common in gardens of	🇺🇸 United States, 🇩🇪 Germany
Invasive in	South Africa (NEMBA 1b), Australia (several states), Argentina: check local rules before planting

Is Honey locust toxic?

People: mildly toxic
Cats: not well documented
Dogs: not well documented
Parts: seeds, unripe pods, thorns

Thorns cause puncture wounds and unripe pods can upset the stomach; pet toxicity is not well documented.

If a child or pet may have eaten part of a plant, call a poison centre or vet straight away.

Companion planting: what to grow with Honey locust

Good neighbours

good With Sweet corn: "Three sisters": climbing beans use corn as a support and fix nitrogen; the benefit to the corn is modest but real in low-input soils. Evidence C

Keep apart or take care

caution With Alliums (onion family): Onions, garlic and leeks are said to stunt beans and peas (allium root exudates may reduce nodulation). Traditional companion-planting advice; controlled trials are few, so treat it as a soft preference. Evidence D
caution With Alliums (onion family): Beans and peas are traditionally kept away from onions, garlic and leeks. Traditional companion-planting advice; controlled trials are few, so treat it as a soft preference. Evidence D
caution With Fennel: Fennel is reported to suppress beans and peas growing next to it. Evidence C

Questions about Honey locust

How far apart should I plant Honey locust?: About 10 m (33 ft) apart, centre to centre. A mature plant spreads 10–15 m (33–49 ft).
Does Honey locust need full sun?: Full sun: at least 6 hours of direct sun a day.
How much water does Honey locust need?: Low water. Drought tolerance is high and waterlogging tolerance moderate.
How cold-hardy is Honey locust?: It tolerates about -34 °C (-29 °F) once established, roughly USDA zone 4.
When does Honey locust flower?: From about June for 1–3 weeks (northern hemisphere; later in cold climates, earlier in warm ones).
Is Honey locust poisonous to cats and dogs?: For cats it is not well documented; for dogs not well documented; for people mildly toxic. Thorns cause puncture wounds and unripe pods can upset the stomach; pet toxicity is not well documented.
What grows well with Honey locust?: "Three sisters": climbing beans use corn as a support and fix nitrogen; the benefit to the corn is modest but real in low-input soils.

Sources and evidence

Evidence grade B (B: extension service or peer-reviewed).

Missouri Botanical Garden Plant Finder, Missouri Botanical Garden
USDA PLANTS Database, USDA NRCS
CABI Invasive Species Compendium, CABI

Notes and assumptions

Plant thornless, podless selections such as Inermis; the wild type is armed with long branched thorns.
Open canopy lets lawn grow underneath; tolerates urban conditions and salt.

Reference values for planning, not horticultural, veterinary or medical advice. Varieties, soils and local climates differ: check with a local nursery or extension service.

Related plants

Bush bean Phaseolus vulgaris
Garden pea Pisum sativum
Sweet pea Lathyrus odoratus
Runner bean Phaseolus coccineus
Broad bean (fava) Vicia faba
Lima bean Phaseolus lunatus
Cowpea (black-eyed pea) Vigna unguiculata
Yardlong bean Vigna unguiculata subsp. sesquipedalis