Climbing euonymus

Year-round

Climbing euonymus (wintercreeper) is an evergreen groundcover or climbing vine originally from East Asia, not a Midwest native, and Iowa State University Extension lists it among landscape plants worth replacing with native groundcovers because it spreads aggressively by rooting runners. In the Des Moines area it tolerates full sun to fairly deep shade and adapts to most garden soils, but it does poorly anywhere the ground stays wet.

• Grows low as a groundcover on its own, but sends out long climbing stems with aerial roots if it reaches a fence, wall, or tree trunk
• Handles full sun to heavy shade and most soil types except consistently wet ground
• Watch for euonymus scale, a hard shelled insect pest that can build up on stems and weaken or kill sections of the planting
• Because it roots as it spreads and can climb into trees, keep it away from wooded edges and check the bed edges periodically
• The ASPCA lists related Euonymus species sold as spindle tree, wahoo, and burning bush as toxic to dogs, cats, and horses (alkaloids and cardenolides, causing vomiting, diarrhea, and in large amounts heart rhythm changes). There is no ASPCA listing specific to this exact species, but since it shares the genus, it is worth keeping pets and grazing animals from eating the leaves or berries

Fall

Fall is the best time in central Iowa to do the yearly cutback and edge on climbing euonymus, both for plant health and for a tidy look going into winter. It is also when the pinkish red seed capsules split open, and since birds and other wildlife carry the seeds into wild areas, cutting off fruiting stems limits how far this non-native plant can spread on its own.

• Trim the planting back to a clean edge along walkways, driveways, and lawn lines before the first hard frost
• Cut off stems carrying the small pink to red seed capsules if you want to limit self seeding into nearby wild or wooded areas
• Remove any stems that climbed a tree, fence, or wall this season, since older climbing growth gets woodier and harder to pull free the longer it is left
• Rework the bed edge now if runners crept into the lawn or a neighboring bed over the summer

A clean fall cutback and edge along walkways and lawn lines reads as intentional care, not neglect, heading into winter.

Winter

Climbing euonymus stays evergreen through central Iowa winters, which means its leaves are exposed to cold, drying wind and bright winter sun that most other perennials never have to deal with. This can cause winter burn, a bronze or brown scorched look on the leaves, especially on plants in open, windy spots or against a south facing wall or driveway.

• Expect some leaf bronzing or browning after a hard winter. This is usually just cosmetic winter burn, not a sign the plant is dead
• Water the plant well in late fall before the ground freezes, since a well hydrated root system handles winter wind better
• When choosing a planting spot, avoid full winter wind exposure or reflected sun off a south facing wall, fence, or driveway if you can help it
• Hold off cutting out winter burned leaves until spring, once new growth shows which stems are still alive

Spring

Spring is when to check climbing euonymus for winter damage and get ahead of pests before the growing season takes off. In central Iowa, evergreen euonymus can look ragged after a hard winter and still leaf out fine, so wait until new growth appears before deciding a stem is dead.

• Cut back brown, bare, or scorched stems only after new growth shows you which wood is still alive
• Trim back any runners that crept past the bed edge the previous season, before they root down again
• Start checking new leaves and stems for euonymus scale, small white or brown bumps, so a light infestation does not turn into a heavy one by summer
• If you divide or transplant a section, water it in and keep the soil evenly moist while it establishes, but do not let it sit waterlogged

Summer

Once established, climbing euonymus in the Des Moines area handles summer heat and short dry spells without much attention, since it is more likely to struggle from wet roots than from drought. Summer is the main window to watch for euonymus scale buildup and to keep climbing stems from reaching structures or trees you do not want covered.

• Water only during extended dry stretches. One deep soaking beats several light waterings
• Check stems through the summer for euonymus scale, a fuzzy looking white or brown crust. Prune out and dispose of the worst sections if you find it
• Walk the bed a few times this season and redirect or cut back any stem that has started climbing a fence, tree trunk, or wall
• Small greenish white flowers appear in early summer but are easy to miss and not a feature most homeowners notice