ENH-768/ST610: Syringa reticulata: Japanese Tree Lilac

Introduction

Though a lilac, this member of the species is kind of completely different in look than these with which gardeners are extra acquainted. Its upright behavior varies from symmetrical to irregular. Cultivars together with ‘Ivory Silk’ and ‘Summer time Snow’ might be used as an alternative of the species as a result of extra constant behavior and extra flowers. This can be a very giant shrub or small tree, reaching a top of about 20 to 30 toes with a 15-foot-spread. The massive clusters of creamy white flowers, borne in early summer time for about two weeks, are the primary decorative characteristic however lack the perfume of the spring-blooming lilacs—this lilac’s perfume is extra suggestive of privet. It’s getting used as a road tree in some elements of the nation, notably in areas with overhead energy strains. Japanese tree lilac can be common as a backyard specimen or as an accent in a shrub border. It deserves to be in any panorama. It offers shade and a colourful spring present for a deck or patio space. Inexperienced fruit clusters are considerably showy when seen from shut vary.

Common Info

Scientific title: Syringa reticulata

Pronunciation: sih-RING-guh reh-tick-yoo-LAY-tuh

Widespread title(s): Japanese tree lilac

Household: Oleaceae

USDA hardiness zones: 4A by way of 7A (Fig. 2)

Origin: not native to North America

Invasive potential: little invasive potential

Makes use of: city tolerant; display; road with out sidewalk; specimen; deck or patio; container or planter; educated as a regular; parking zone island < 100 sq ft; parking lot island 100-200 sq ft; parking lot island > 200 sq ft; sidewalk cutout (tree pit); tree garden 3-Four toes extensive; tree garden 4-6 toes extensive; tree garden > 6 ft extensive; freeway median

Availability: considerably obtainable, might must exit of the area to search out the tree

Description

Peak: 20 to 30 toes

Unfold: 15 to 25 toes

Crown uniformity: irregular

Crown form: upright/erect, spherical, vase

Crown density: dense

Progress price: reasonable

Texture: medium

Foliage

Leaf association: reverse/subopposite (Fig. 3)

Leaf kind: easy

Leaf margin: whole, undulate

Leaf form: ovate

Leaf venation: pinnate, brachidodrome

Leaf kind and persistence: deciduous

Leaf blade size: 2 to Four inches, Four to eight inches

Leaf coloration: inexperienced

Fall coloration: no coloration change

Fall attribute: not showy

Flower

Flower coloration: white/cream/grey

Flower traits: very showy

Fruit

Fruit form: elongated, oval

Fruit size: .5 to 1 inch

Fruit protecting: dry or laborious

Fruit coloration: yellow, inexperienced

Fruit traits: doesn’t appeal to wildlife; showy; fruit/leaves not a litter drawback

Trunk and Branches

Trunk/bark/branches: branches droop; showy; sometimes multi-trunked; thorns

Pruning requirement: little required

Breakage: resistant

Present yr twig coloration: brown

Present yr twig thickness: thick

Wooden particular gravity: unknown

Tradition

Mild requirement: full solar

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

Drought tolerance: reasonable

Aerosol salt tolerance: excessive

Different

Roots: not an issue

Winter curiosity: sure

Excellent tree: sure

Ozone sensitivity: unknown

Verticillium wilt susceptibility: vulnerable

Pest resistance: immune to pests/ailments

Use and Administration

The tree is offered as a multi-stemmed specimen or as a single-trunked road tree. The trunk might be educated to develop pretty straight to 10 toes after which branches right into a stiff, upright, rounded head of foliage. The bark is considerably showy with outstanding lenticels, being paying homage to black cherry. As with different lilacs, the plant as a shrub might have rejuvenation by pruning each few years because it turns into overgrown. It’s maybe essentially the most pest-resistant lilac, however that doesn’t imply it’s pest-free. Common irrigation throughout dry spells assist make this a pest-resistant tree.

Japanese tree lilac is tolerant of city situations, rising in poor, clay, or alkaline soil. The beautiful flowers are most showy and prolific when the tree is situated in full solar with good drainage. Vegetation in partial shade might be contaminated with powdery mildew which may trigger some defoliation.

Obtainable cultivars embody: ‘Ivory Silk’—grows in USDA hardiness zones Three to six, upright oval, good flowers, borne in alternate years; ‘Summer time Snow’—grows in USDA hardiness zones Three to six, upright, spherical form, persistent seed pods.

Pests

If correctly situated on an applicable web site, there are few issues.

Lilac borer larvae tunnel within the branches, inflicting wilting, notably on drought-stressed bushes. Severely infested branches might break off. Take away and destroy infested stems. Maintain vegetation wholesome with common waterings throughout dry climate and by fertilizing.

Lilac leaf miner tunnels within the leaves in early summer time. After mining the leaf, the caterpillars emerge and net leaves collectively and skeletonize the foliage. Mild infestation might be managed by hand selecting.

Scales are most frequently discovered infesting the decrease stems and sometimes mix in with the bark. Examine unhealthy-looking vegetation for scale infestations. Spray with horticultural oil to regulate overwintering phases.

Illnesses

It’s often free of great illness.

Bacterial blight is most critical on white flowered alternatives. The younger shoots develop black stripes or one facet of the shoot turns black. Spots develop on the leaves, forming a water-soaked blotch. Younger leaves flip black and die shortly. On older shoots, the spots enlarge extra slowly. The flowers wilt and darken. The illness is worse when moist climate happens as the brand new shoots are creating. Skinny the crown to extend air circulation. Take away and destroy diseased shoots and keep away from extreme nitrogen fertilizer.

Phytophthora blight kills stems to the bottom. The leaves flip black and shoots have brown lesions on them.

Leaf blotch causes zoned, brown spots. The contaminated space drops out, leaving a gap within the leaf.

Many fungi trigger leaf spots.

Powdery mildew coats the leaves with white powder. Throughout moist climate, lilacs mildew simply. Mildew is particularly extreme on shade-grown vegetation. Ignore late season infections.

Verticillium wilt causes wilting and untimely leaf drop. The illness might kill one, a number of or all of the branches. Attempt fertilizing frequently to assist stop ailments.

Bacterial crown gall causes spherical, warty galls on the stems close to the soil line. Take away contaminated vegetation and don’t replant with a delicate tree in the identical spot.

---

U.S. Division of Agriculture, UF/IFAS Extension Service, College of Florida, IFAS, Florida A & M College Cooperative Extension Program, and Boards of County Commissioners Cooperating. Nick T. Place, dean for UF/IFAS Extension.