Sweetgum

Sun

Full sun for the strongest autumn colour; tolerates light partial shade.

Water

Keep young trees evenly moist. Established trees tolerate short dry spells, but prolonged drought can cause leaf scorch and early leaf fall.

Soil

Deep, moist, acidic to neutral soil, preferably well drained. Tolerates clay and occasional waterlogging; alkaline or chalky soil often causes yellow leaves and poor growth.

Height

60-80 ft (18-24 m)

Spread

40-60 ft (12-18 m)

Flowers

Small, inconspicuous greenish flowers in spring; female flowers develop into woody, spiny seed balls.

Foliage

Glossy green, star-shaped leaves, usually with five to seven pointed lobes; autumn colour varies with the tree, soil and weather. Twigs may develop corky ridges.

Growth

Moderate to fast when young, slowing with age.

Care needed

Medium

• Heat tolerant
• Wildlife

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

Difficulty

Moderate

Toughness

Fairly tough

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

1. Planting day

   8 ft (2.5 m)

2. After 1 year

   11 ft (3.4 m)

3. After 2 years

   14 ft (4.4 m)

4. After 3 years

   17 ft (5.3 m)

5. After 5 years

   23 ft (7.1 m)

About 20 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

Growth rate

Moderate

• Plant while dormant, choosing a small nursery tree because larger specimens can be difficult to establish.
• Water deeply during dry spells for the first two to three growing seasons.
• Spread a 2-3 in (5-8 cm) layer of organic mulch over the root area, keeping it clear of the trunk.
• Leave room for the mature crown and spreading roots; avoid planting beside paving, drains or small terraces.
• Do not feed routinely; use a soil test to guide treatment if growth is poor or leaves turn yellow.
• Collect fallen seed balls from paths and lawns where people walk or play.

Pruning. Prune in late winter while dormant, removing dead, damaged or crossing branches and correcting competing leaders while the tree is young. Avoid topping or heavy crown reduction; use a qualified arborist for large branches.

Autumn

Plant after leaf fall while the soil remains workable, or wait until spring in very cold regions.

Late winter

Check young trees for competing leaders and prune lightly to develop a sound framework.

Spring

Refresh mulch and check that ties are not rubbing or constricting the trunk.

Late spring

Check new leaves for yellowing between green veins, especially on alkaline soil.

Summer

Water young trees deeply during dry weather and check established trees for drought stress.

Autumn and winter

Rake leaves and remove fallen seed balls from walking routes; seed balls may continue dropping for months.

• Use as a specimen in a large lawn, leaving ample room for its broad mature crown.
• Plant at a woodland edge with acid-soil shrubs for layered autumn colour.
• Use in spacious parkland or estate avenues where roots and seed litter will not conflict with paving.
• Place beyond a terrace or main window to frame a seasonal view without overhanging the seating area.

Garden styles it suits: Grand estate, Woodland, Traditional, Autumn colour, Southern and English country.

Plant it with: Oakleaf hydrangea, Fothergilla, Virginia sweetspire, Rhododendron, Christmas fern and Pennsylvania sedge.

Wildlife: Seeds feed finches and other small birds, and the mature crown provides shelter and nesting sites. The leaves support caterpillars within its native range.

• Yellow leaves with green veins usually indicate iron chlorosis on alkaline soil: test soil pH, avoid planting on chalk, and seek advice on suitable chelated iron treatment; repeated treatment may not overcome an unsuitable site.
• Leaf scorch and premature leaf drop can follow drought or root disturbance: water deeply, mulch and avoid digging or compacting soil beneath the crown.
• Surface roots can lift paving and root suckers may appear: allow generous planting space, remove suckers at their origin and do not cut major roots to protect paving.
• Spiny seed balls create persistent litter and can be uncomfortable underfoot: collect them regularly and keep the species away from busy paths and play areas.

Not known to be toxic to people, cats, dogs or horses. The hard, spiny seed balls are a physical hazard rather than a poison: they can hurt paws or bare feet and may cause choking or digestive injury if swallowed.

• Japanese maple (Acer palmatum)

  Both can have deeply lobed leaves, but maple leaves and buds occur in opposite pairs. Sweetgum leaves alternate along the twig, and its fruit is a spiny ball rather than paired winged seeds.

• London plane (Platanus × hispanica)

  London plane has broader, less sharply star-shaped leaves, conspicuously peeling mottled bark and fuzzy-looking seed balls. Sweetgum has sharply pointed leaf lobes and hard, visibly spiny fruit.

• Chinese sweetgum (Liquidambar formosana)

  Chinese sweetgum usually has three-lobed leaves, often hairy beneath, whereas American sweetgum usually has five to seven lobes and largely hairless mature leaves.

Liquidambar combines Latin liquidus, meaning liquid, with Arabic anbar, referring to amber, while styraciflua means flowing with storax, alluding to the fragrant resin that also gives sweetgum its common name.

Propagation. Grow from seed collected from ripe seed balls; a period of cold, moist stratification improves germination. Seedlings vary in autumn colour. Named cultivars are usually propagated by grafting to preserve their characteristics.

Accepted botanical name

Liquidambar styraciflua

In the US and Canada

Native in the lower 48 states.

Native range

Alabama, Arkansas, Belize, Connecticut, El Salvador, Florida, Georgia, Guatemala, Honduras, Illinois, Indiana and Kentucky.

Measured

Soil pH 4.5 to 7. Average height 1840 cm.

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