Buttonbush

Sun

Full sun to partial shade; flowering is best in full sun.

Water

Keep the soil consistently moist to wet. Established plants tolerate periodic flooding and shallow standing water, but prolonged drought causes stress.

Soil

Moisture-retentive loam, clay or silty soil, preferably acidic to neutral. Tolerates poorly drained ground.

Height

6-12 ft (1.8-3.7 m), occasionally taller in favourable wet sites

Spread

4-8 ft (1.2-2.4 m)

Flowers

Summer to early autumn; fragrant, creamy-white spherical flower heads with projecting styles.

Foliage

Glossy green, oval leaves arranged in opposite pairs or whorls of three; autumn colour is usually yellow and can be modest.

Growth

Moderate to fast with adequate moisture

Care needed

Low

• Pollinators
• Deer resistant
• Heat tolerant
• Wildlife
• Low allergen
• Fragrant

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

Difficulty

Easy

Toughness

Fairly tough

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

1. Planting day

   1.6 ft (0.5 m)

2. After 1 year

   3 ft (1.1 m)

3. After 2 years

   5 ft (1.6 m)

4. After 3 years

   7 ft (2.2 m)

5. After 5 years

   9 ft (2.8 m)

   full size

About 4 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

Toxic

Native to

the US and Canada

Growth rate

Fast

• Plant where the root zone stays moist, allowing room for a broad, multi-stemmed shrub.
• Water deeply during establishment and whenever the soil starts drying during prolonged dry weather.
• Apply 2-3 in (5-8 cm) of organic mulch, keeping it clear of the stems.
• On ordinary garden soil, use a light spring dressing of compost; routine fertiliser is usually unnecessary.
• Remove unwanted suckers if the shrub begins spreading beyond its allotted space.

Pruning. Prune in late winter or early spring, removing dead wood and thinning crowded stems at ground level. Flowers form on new growth, so an overgrown shrub can be cut back hard at this time, although routine hard pruning is unnecessary.

Late winter

Remove dead or crossing branches and thin older stems if the centre is crowded.

Early spring

Plant while dormant or just before growth begins, then water thoroughly.

Spring

Refresh the mulch and add a light dressing of compost if the soil is poor.

Early summer

Check soil moisture as temperatures rise, especially around newly planted shrubs.

Summer

Water during dry spells and avoid spraying insecticides on flowers visited by pollinators.

Autumn

Leave the rounded seed heads for birds and seasonal interest; remove unwanted seedlings or suckers.

• Plant along pond margins to soften the transition between water and garden.
• Use in the wetter part of a rain garden with sedges and moisture-loving perennials.
• Group along a sunny woodland edge for an informal flowering shrub layer.
• Combine with Joe-Pye weed and swamp milkweed for a tall, summer-flowering pollinator planting.

Garden styles it suits: Bog garden, Wildlife garden, Pollinator garden, Woodland, Rewilded and New England.

Plant it with: Swamp milkweed, Joe-Pye weed, Blue flag iris, Tussock sedge, Cardinal flower and Winterberry holly.

Wildlife: The nectar-rich flowers attract bees, butterflies and other pollinating insects. Waterfowl and some other birds eat the seeds, while dense branches provide shelter near water. It is native across much of eastern and central North America, with additional populations farther west and south.

• Leaf scorch, wilting or early leaf drop in dry soil: water deeply, renew mulch and move the shrub if the site is persistently too dry.
• Sparse flowering in heavy shade: move to a sunnier position or reduce nearby shading where practical.
• Leaf spots in humid conditions: collect badly affected fallen leaves and thin crowded growth; established shrubs rarely need fungicide.
• Unwanted suckers or seedlings in wet ground: remove them while small and allow adequate space around the parent shrub.

Leaves and bark contain toxic compounds, and poisoning is documented in livestock, including horses. Ingestion can cause gastrointestinal and nervous-system symptoms and may be serious or fatal in quantity. Treat the plant as poisonous to people; specific evidence for cats and dogs is limited, so keep pets from chewing it and seek medical or veterinary advice after ingestion.

• Buttonwood (Conocarpus erectus)

  Despite the similar common name, buttonwood is a frost-tender coastal shrub or tree with alternate, leathery leaves and small cone-like fruit clusters.

Cephalanthus combines Greek words for 'head' and 'flower', referring to the spherical flower heads, while occidentalis means 'western'.

Propagation. Take softwood cuttings in early summer or separate rooted suckers while dormant. Seed can be sown in autumn and exposed to winter cold; seedlings vary and will not reliably reproduce named cultivars.

Accepted botanical name

Cephalanthus occidentalis

In the US and Canada

Native in Canada and the lower 48 states.

Native range

Alabama, Arizona, Arkansas, Belize, California, Connecticut, Cuba, Florida, Georgia, Guatemala, Honduras and Illinois.

Measured

Average height 190 cm.

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