Gleditsia triacanthos 'Shademaster' is a large thornless honey locust grown for its fine pinnate foliage and even, spreading crown. The leaflets are small and ferny, so the canopy filters light rather than blocking it. Fresh green in spring and summer, the foliage turns yellow through autumn before falling.
It performs in full sun to part shade across cool temperate, temperate and semi arid districts, taking frost, heat, wind and compacted urban soil in its stride. Growth is 30 to 60 centimetres a year. Once established it is drought tolerant and needs little beyond formative pruning in the early seasons.
This is a park and street tree first. Councils plant it along roads and through car parks, and it works over lawns and paved courtyards where dappled shade is wanted without heavy litter. On a larger residential block it will shade a house within a decade of planting.
Frequently Asked Questions
About Gleditsia 'Shademaster'
What is Gleditsia triacanthos 'Shademaster'?
It is a named thornless cultivar of the honey locust, selected for a uniform upright branching pattern and an even, spreading crown. It suits Australian street and park planting because it takes hard urban conditions, casts light dappled shade, and carries fine ferny foliage that colours yellow in autumn before it drops.
How big does Shademaster Honey Locust grow?
At maturity it reaches 12 to 18 metres tall with a canopy spread of 8 to 15 metres, making it a genuine large shade tree. Allow that room at planting, well clear of buildings and overhead wires. On a restricted site, a compact honey locust selection is the better fit.
How fast does it grow?
Around 30 to 60 centimetres a year, faster in deep soil with summer moisture. An advanced tree puts on useful canopy within three or four seasons, which is why it is specified where shade is needed reasonably quickly. Growth slows as the tree approaches full height, and the crown then broadens rather than climbs.
Does it produce seed pods?
Very few. 'Shademaster' was selected in part for setting little to no fruit, so the long brown pods that litter the ground under seedling honey locusts are not an issue here. Small greenish flowers appear in spring and are barely noticeable. Autumn leaf drop is fine textured and breaks down fast.
Is it suitable for street and car park planting?
Yes, it is one of the standard choices. It tolerates compacted soil, reflected heat off asphalt, exhaust pollution and root restriction, and it has no thorns to catch pedestrians. The high branching habit clears vehicles and sight lines once the tree has been formatively pruned. Give the roots adequate soil volume.
Will grass grow underneath it?
Usually yes. The leaflets are small and widely spaced, so light filters through and the shade beneath is dappled rather than dense. Lawn, groundcovers and shade tolerant shrubs all grow underneath, which is unusual for a tree of this size. That quality is why it is used over turf and seating areas.
How do I care for Shademaster Honey Locust?
Water deeply through the first two or three summers, then it manages on rainfall in most temperate districts. Formative prune in the early years to establish a single leader and a clear trunk. After that, remove deadwood in late winter. Mulch annually and feed in early spring if growth looks slow.