x Hesperotropsis leylandii 'Naylor's Blue': 'Naylor's Blue' Leyland Cypress

Edward F. Gilman, Dennis G. Watson, Ryan W. Klein, and Deborah R. Hilbert


Introduction

A moderate to rapidly growing evergreen when young, ‘Naylor's Blue' Leyland cypress will easily grow three feet per year, even on poor soils, and will ultimately attain a majestic height of 50 feet or more in the west, perhaps somewhat shorter in the east. Leyland cypress forms a dense, oval, or pyramidal outline when left unpruned, but the graceful, pendulous branches will tolerate severe trimming to create a formal hedge, screen, or windbreak. The fine, feathery glaucous blue-green foliage is composed of soft, pointed leaves on flattened branchlets and are dark blue-green when mature. Leyland cypress quickly outgrows its space in small landscapes and is too big for most residential landscapes unless it will be regularly trimmed. Although it can be sheared into a tall screen on small lots, Leyland cypress should probably be saved for large-scale landscapes where it can be allowed to develop into its natural shape.

Middle-aged x Hesperotropsis leylandii 'Naylor's Blue': 'Naylor's Blue' leyland cypress.
Figure 1. Middle-aged x Hesperotropsis leylandii 'Naylor's Blue': 'Naylor's Blue' leyland cypress.
Credit: UF/IFAS

General Information

Scientific name: x Hesperotropsis leylandii

Pronunciation: x hes-per-oh-trop-sis lay-LAN-dee-eye

Common name(s): 'Naylor's Blue' Leyland Cypress

Family: Cupressaceae

USDA hardiness zones: 6A through 10A (Figure 2)

Origin: not native to North America

Invasive potential: not assessed/incomplete assessment

Uses: specimen; screen; hedge; highway median; Christmas tree

Range
Figure 2. Range
Credit: UF/IFAS

Description

Height: 40 to 50 feet

Spread: 15 to 25 feet

Crown uniformity: symmetrical

Crown shape: oval, pyramidal, columnar

Crown density: dense

Growth rate: fast

Texture: fine

Foliage

Leaf arrangement: opposite/subopposite

Leaf type: simple

Leaf margin: entire

Leaf shape: scale-like

Leaf venation: none, or difficult to see

Leaf type and persistence: evergreen

Leaf blade length: less than 2 inches

Leaf color: blue or blue-green

Fall color: no color change

Fall characteristic: not showy

Flower

Flower color: no flowers

Flower characteristics: no flowers

Fruit

Fruit shape: round

Fruit length: less than .5 inch

Fruit covering: dry or hard

Fruit color: brown

Fruit characteristics: does not attract wildlife; not showy; fruit/leaves not a litter problem

Trunk and Branches

Trunk/bark/branches: branches don't droop; not showy; typically one trunk; thorns

Pruning requirement: little required

Breakage: resistant

Current year twig color: green

Current year twig thickness: thin

Wood specific gravity: unknown

Culture

Light requirement: full sun, partial sun, or partial shade

Soil tolerances: sand; loam; clay; acidic; alkaline; well-drained

Drought tolerance: high

Aerosol salt tolerance: moderate

Other

Roots: not a problem

Winter interest: no

Outstanding tree: yes

Ozone sensitivity: unknown

Verticillium wilt susceptibility: resistant

Pest resistance: sensitive to pests/diseases

Use and Management

Leyland cypress grows in full sun on a wide range of soils, from acid to alkaline, but looks its best on moderately fertile soil with sufficient moisture. It is surprisingly tolerant of severe pruning, recovering nicely from even severe topping (although this is not recommended), even when half the top is removed. It grows well in clay soil and tolerates poor drainage for a short period of time. It also is very tolerant of salt spray.

Some other cultivars include: ‘Castlewellan', a more compact form with gold-tipped leaves, excellent for hedges in cool climates; ‘Leighton Green', dense branching with dark green foliage, columnar form; ‘Haggerston Gray', loose branches, columnar-pyramidal, upturned at ends, sage-green color; ‘Silver Dust', wide-spreading form with blue-green foliage marked with white variegations.

Propagation is by cuttings from side growths.

Pests

Bagworm can defoliate a tree in a week or two and can be quite serious.

Diseases

A canker affects the tree following drought; a foliage fungus occasionally infects foliage. This plant is not recommended for planting in California due to the severity of this canker disease. Perhaps the disease will stay in the western United States.