Manhattan euonymus is a glossy-leaved evergreen shrub prized for forming a dense hedge or screen with little fuss. It is tough enough to handle city air, dust, and even blasts from farm ventilation fans.1USDA NRCS. Plants Tolerant of Poultry Farm Emissions in the Chesapeake Bay Watershed It isn’t trouble-free, though. The problems owners notice most are tied to climate and to a couple of familiar pests rather than to difficult care.
How Big Manhattan Euonymus Gets and How Fast
Manhattan is a compact selection of spreading euonymus, whose parent grows into an 8 to 10 foot rounded shrub.2NC State Extension Plants. Euonymus kiautschovicus Manhattan Manhattan itself usually matures at 4 to 6 feet tall and 3 to 5 feet wide in an upright, rounded shape.3Missouri Botanical Garden. Euonymus kiautschovicus Manhattan Some plants reach 8 feet, and nurseries list spreads up to 5 to 8 feet.4Plant Addicts. Manhattan Euonymus In sheltered spots with years to grow, older plants can approach 10 feet tall and wide.5USDA NRCS. Plants Tolerant of Poultry Farm Emissions in the Chesapeake Bay Watershed
Climate and pruning change the final size, which is why nursery tags disagree. Colder areas with winter dieback keep plants smaller, while unpruned plants in mild, sheltered sites end up at the top of the range. If you won’t prune regularly, plan your spacing for the larger figure.
Space it for at least 5 feet of width so it doesn’t crowd walks or windows. For a hedge, go by the plant’s mature width. A planting meant to merge into one wall can sit closer than a lone specimen that should show its full rounded shape. Check the distance to a fence, wall, or foundation too, because a crowded shrub has to be cut back hard to fit.
It grows quickly, reaching its natural form sooner than most hedge shrubs.6Monrovia. Manhattan Euonymus The leaves are glossy dark green, slightly leathery, about 2 1/2 inches long with finely toothed edges.7Oregon State University Landscape Plants. Euonymus × kiautschovicus ‘Manhattan’ The shrub is semi-evergreen, which means it keeps some, not all, of its leaves through winter in colder areas. In warm-winter areas it stays fully green year-round.
Greenish-white flower clusters appear in July and August and draw bees and flies.8Missouri Botanical Garden. Euonymus kiautschovicus Manhattan Pink seed capsules then open in fall to show red seeds, maturing around November.9Missouri Botanical Garden. Euonymus kiautschovicus Manhattan
Where to Plant It, Climate, Light, Soil and Water
Manhattan euonymus grows in USDA zones 5 to 8. A USDA zone is a band on a map based on the average coldest winter temperature.10Missouri Botanical Garden. Euonymus kiautschovicus Manhattan Some regard Zone 5 as marginal and rate the shrub reliably hardy from Zone 6.11Oregon State University. Euonymus × kiautschovicus ‘Manhattan’ In Zone 5, plant it in a spot sheltered from winter wind.
You can find your zone by looking up your zip code on the USDA map. A zone is an average, so an unusually cold winter can still dip below it.
Full sun to part shade both work. Deep, humid shade encourages powdery mildew, covered later, so avoid tucking the shrub into a damp, still corner.
It needs moderate water and becomes drought-resistant once established.12Boething Treeland Farms. Euonymus kiautschovicus ‘Manhattan’ Water deeply through the first growing season, then mainly in long dry spells. Related euonymus turns yellow between the veins when short of iron.13Journal of Plant Nutrition. Iron nutrition of the broadleaf evergreen shrub,Euonymus japonicathunb If new leaves yellow while the veins stay green, especially on alkaline soil, an iron problem is likely and a soil test is worth doing.
For a hedge, dig each hole as deep as the root ball and twice as wide. Set the top of the roots level with the soil, not buried. Mulch two to three inches deep, keeping it off the stems.
The shrub is highly tolerant of urban pollution and can thrive in inner-city spots.14Millcreek Gardens. Manhattan Spreading Euonymus (Euonymus kiautschovicus ‘Manhattan’) Planted just 20 to 40 feet from poultry-house fans, every test plant survived the dust and ammonia.15USDA NRCS. Plants Tolerant of Poultry Farm Emissions in the Chesapeake Bay Watershed It still does best in a relatively sheltered location.16Millcreek Gardens. Manhattan Spreading Euonymus (Euonymus kiautschovicus ‘Manhattan’)
Why Leaves Turn Yellow or Drop in Winter
In cold-winter areas, Zones 5 and 6, leaves may turn yellow or drop and plants may die back to the ground.17Missouri Botanical Garden. Euonymus kiautschovicus ‘Manhattan’ Even in a mild climate like western Oregon, it can drop more leaves than Japanese euonymus, leaving yellow-green foliage.18Oregon State University. Euonymus × kiautschovicus ‘Manhattan’ A sparse, yellowish shrub in late winter is usually still alive.
To check, scratch a stem. Use a thumbnail or the tip of a knife to scrape away a small patch of outer bark on a twig. Green, moist tissue underneath means the stem is alive, while brown and dry tissue means that part is dead. Test several stems at different heights, because a plant can have live lower wood and dead tips.
After a hard winter, wait until new growth starts before cutting anything. Then prune stems that stay brown and brittle back to live wood. Plants that died to the ground often resprout from the base. In exposed sites, a layer of mulch protects the roots.
Winter yellowing affects the whole plant fairly evenly after a cold spell. Disease looks different, with spots, white powder, or bumps on leaves and stems. Yellowing from scale persists into summer rather than greening up.
Pruning and Shaping a Manhattan Euonymus Hedge
Because it grows quickly, it handles shaping and keeps growing back.19Plant Addicts. Manhattan Euonymus Left unsheared, it shows its natural form and pink fall fruit.20Monrovia. Manhattan Euonymus Shearing cuts all the outer tips to one surface and gives a tidy formal line, but it removes many flowers and fruit and creates dense outer growth. Selective pruning means cutting individual stems back to a branch or to the base, which keeps a looser shape and leaves more of the fall fruit. For a natural screen that isn’t meant to look clipped, selective cuts once a year are usually enough. Every cut is a wound that soil bacteria can use to cause crown gall.21Pacific Northwest Pest Management Handbooks. Euonymus-Crown Gall Use clean, sharp tools and avoid ragged cuts.
Do major shaping in late winter or early spring, before new growth. Light trims through summer keep a formal hedge neat. Keep the base slightly wider than the top so light reaches the lower leaves. Stop heavy pruning by late summer so new shoots harden before cold.
An overgrown shrub can be renewed by removing the oldest thick stems at the base over two or three years. Its fast growth means it fills back in quickly, and the thinning improves air flow, which helps against mildew.
Euonymus Scale and Other Pests
Euonymus scale is a tiny, shelled insect that sticks to stems and leaves and sucks plant sap. It feeds inside leaves, leaf stalks, and stems, reaching the water-carrying tissue in stems.22Annals of the Entomological Society of America. Use of host plant resources by the Euonymus scale, Unaspis euonymi (Homoptera: Diaspididae) Heavy infestations show up as yellow-spotted leaves and dying branches.
Scale is hard to notice because the insects are small and sit still under a hard covering, so they look like part of the bark or a plant growth and not like insects. A heavily infested stem can look crusty or gray-white from the layers packed together. When leaves yellow in patches, look at the stems.
Look for white, rice-like specks (males) and brown, shell-shaped bumps (females). Check the undersides of leaves and the inner branches first. Yellow blotches on upper leaf surfaces often sit above scale colonies.
Cut out and bag heavily covered branches. Spray horticultural oil in late winter to smother overwintering scale. Treat young crawlers in late spring with oil or insecticidal soap. Scale returns readily, so check again every year.
Powdery Mildew, Leaf Spot and Crown Gall
Powdery mildew forms gray-white powdery mats on both leaf surfaces.23WSU Extension Hortsense. Euonymus: Powdery mildew Affected leaves may twist, yellow, and drop.24WSU Extension Hortsense. Euonymus: Powdery mildew It thrives in shade and humid weather with warm days and cool nights.25WSU Extension Hortsense. Euonymus: Powdery mildew It spreads most at 70 to 80°F with humidity above 85%, yet rain and wet leaves actually suppress it.26Pacific Northwest Pest Management Handbooks. Euonymus-Powdery Mildew The fungus overwinters on fallen leaves and the plant,27WSU Extension Hortsense. Euonymus: Powdery mildew so rake up fallen leaves and improve air flow. On related euonymus, baking-soda solutions with horticultural oil controlled mildew.28HortScience. Controlling Powdery Mildew in Euonymus with Polymer Coatings and Bicarbonate Solutions
A common home recipe is about one tablespoon of baking soda with a little horticultural oil per gallon of water. Spray all leaf surfaces at the first sign of powder. Test on a few leaves first, and avoid spraying in hot sun.
Leaf spot shows as small brown spots with pale centers and brown marks on young twigs.29Home & Garden Information Center. Euonymus Diseases and Insect Pests in South Carolina Severe cases cause early leaf drop.30Home & Garden Information Center. Euonymus Diseases and Insect Pests in South Carolina Variegated euonymus types are more susceptible than solid green ones like Manhattan.31Home & Garden Information Center. Euonymus Diseases and Insect Pests in South Carolina
Crown gall causes rough, knobby swellings at the soil line.32University of Arkansas Division of Agriculture. Euonymus Crown Gall Soil bacteria enter through wounds from tools, pruning, insects, or frost heaving.33Pacific Northwest Pest Management Handbooks. Euonymus-Crown Gall Avoid nicking the base with mowers and trimmers.
Galls can’t be cured once they form. Mildly affected plants can live for years. Remove badly declining plants along with the surrounding soil, and don’t replant susceptible shrubs in the same spot.
Is Manhattan Euonymus Poisonous to Pets and People
The leaves and seeds contain toxins, including heart-affecting compounds.34Pet Poison Helpline. Euonymus Is Toxic To Cats A pet eating a few leaves or seeds usually gets vomiting, diarrhea, or drooling.35Pet Poison Helpline. Euonymus Is Toxic To Cats Eating a large amount can cause an irregular heartbeat, weakness, and collapse.36Wag!. Euonymus Poisoning in Dogs – Symptoms, Causes, Diagnosis, Treatment, Recovery, Management, Cost If a pet eats the plant, call a vet or pet poison line.
Pets that chew on hedge trimmings are exposed too, so rake up clippings and don’t leave them within reach. The plant stays toxic after cutting, so a compost pile a dog can reach is a poor place for trimmings.
Pick off fruit near play areas if needed, and teach children not to eat berries from shrubs. If a child eats any, call poison control right away.
Will It Spread Like Burning Bush
Burning bush, a related euonymus, forms dense thickets in woodlands by root suckering, rooting stems, and abundant fruit.37Ohio State University Extension. Controlling Non-Native Invasive Plants in Ohio Forests: Winged Burning Bush (Euonymus alatus) It spreads when birds and other animals eat the fruit and drop seeds in woods. Manhattan is grown widely as a hedge without the same reputation, though its fall fruit also carries seeds.
To keep it contained, check under the hedge each spring for seedlings and cut back low branches that touch and root in soil. Native shrub alternatives exist if you border natural areas. Rules differ between regions, so a local extension office or state invasive plant list is the best place to check before planting near natural land.