What hardiness zones is Corylus colurna suitable for?

Corylus colurna is suitable for USDA hardiness zones 4, 5, 6, 7, 8.

What are the sun requirements for Corylus colurna?

Corylus colurna requires Full Sun.

How much water does Corylus colurna need?

Corylus colurna has Low water needs.

Broadleaf Deciduous Trees

Corylus colurna

Turkish Hazelnut

Betulaceae

Southeastern Europe and western Asia (Balkans, Turkey, Iran)

At a Glance

TypeTree

HabitUpright

FoliageDeciduous

Height40-60 feet (12-18 m)

Width20-30 feet (6-9 m)

Maturity30 years

Growing Zones

USDA Hardiness Zones

4 - 8

Zone 4

Zone 5

Zone 6

Zone 7

Zone 8

These zones indicate the coldest temperatures this plant can typically survive.

Frost Tolerancehardy

Key Features

Attracts Pollinators

Drought Tolerant

Maintenancevery low

Overview

Corylus colurna is a medium to large, symmetrically pyramidal, deciduous tree reaching 40–60 feet (12–18 m) tall with a spread of 20–30 feet (6–9 m). Unlike the multi-stemmed, shrubby European hazel (C. avellana), this species develops a single, straight trunk with a symmetrical, pyramidal to conical crown—one of the most formally structured native trees of southeastern Europe. The bark is corky and deeply furrowed on mature trunks. Yellowish catkins 2–3 inches (5–8 cm) long dangle from branches in February–March. Leaves are broadly ovate, 3–6 inches (8–15 cm) long, dark green, coarsely doubly serrate. Small edible hazelnuts are enclosed in thick, fringed, spiny involucres (husks). Fall color is yellow. Growth rate is moderate at 12–18 inches (30–45 cm) per year. Highly tolerant of urban conditions—heat, drought, poor soil, alkaline soil, and pollution. No significant pest or disease problems. Resistant to eastern filbert blight. The symmetrical pyramidal form and urban tolerance make this an underused street tree.

Native Range

Corylus colurna is native to southeastern Europe and western Asia, from the Balkans through Turkey to Iran, occurring in mountain forests from 1,500 to 6,000 feet (450–1,800 m).

Suggested Uses

Planted as a street tree, shade tree, and specimen in urban landscapes, parks, and large gardens at 20–25 foot (6–7.5 m) spacing. The symmetrical pyramidal form, urban tolerance, and disease resistance make this one of the most reliable underused street trees. Functions in parking lot islands, median strips, and plazas where heat and poor soil challenge other species. The corky bark and pendulous catkins provide winter interest. Not suitable for small gardens due to the large mature size.

How to Identify

Distinguished from C. avellana by the single-trunked tree form (versus multi-stemmed shrub), the larger size (40–60 feet / 12–18 m versus 8–15 feet / 2.4–4.5 m), the corky bark, and the spiny nut husks. Distinguished from Carpinus betulus (European hornbeam) by the catkins (versus hop-like fruit clusters), the corky bark, and the coarser leaf texture. The symmetrically pyramidal, single-trunked tree with corky bark and pendulous winter catkins is diagnostic.

Appearance

Size & Dimensions

Height40' - 60'

Width/Spread20' - 30'

Reaches mature size in approximately 30 years

Colors

Flower Colors

yellow

Foliage Colors

green

Fall Foliage Colors

yellow

Bloom Information

Bloom Period

~4 weeks

WinterSpring

Pendulous, yellowish catkins 2–3 inches (5–8 cm) long appear on bare branches in February–March. Small, red female flowers at bud tips. Small edible hazelnuts in thick, spiny involucres ripen in fall. Bloom duration is 3–4 weeks.

Detailed Descriptions

Flower Description

Yellowish pendulous catkins

Foliage Description

Dark green, broadly ovate, coarsely doubly serrate, 3-6 inches

Growing Conditions

Sun Requirements

Full Sun

Requires 6-12 hours of direct sunlight daily

• Full Sun: 6+ hours of direct sunlight

• Partial Shade: 3-6 hours of direct sunlight

• Full Shade: Less than 3 hours of direct sunlight

Soil Requirements

pH Range5.5 - 8.0(Neutral)

357912

Soil Types

loamclaysandchalk

Drainage

well drained

Water & Climate

Water Needs

Low

Frost Tolerance

hardy

Time to Maturity

10-15 years

Drought Tolerance

Drought tolerant when established

Care & Maintenance

Care Guide

Plant in full sun in average to poor, well-drained soil. Tolerates alkaline, clay, and compacted soils. Drought-tolerant once established. Highly tolerant of urban conditions including heat island effect, reflected heat, restricted root space, and air pollution. Transplants readily. No significant pest or disease problems. Resistant to eastern filbert blight—unlike C. avellana. Minimal maintenance once established.

Pruning

Minimal pruning. Remove dead, crossing, or damaged branches in late winter. Train to a central leader when young. The symmetrical pyramidal form develops naturally without corrective pruning. Remove lower limbs for pedestrian clearance as needed.

Pruning Schedule

winter

Maintenance Level

very low

⚠️ Toxicity Warning

Non-toxic