Russian Olive (Elaeagnus angustifolia)

Euonymus is a diverse shrub group and comes in many shapes, sizes, and colors, but whatever variety you select, you are in for a show. This hardy plant can be deciduous or a broadleaf evergreen; some cultivars, like Burning Bush, grow about 3 feet tall and have an upright, branching structure, while others, like wintercreeper, have a lower profile and reach about 1 foot tall. Euonymus is commonly selected for its lovely and sometimes showy foliage.

I. Appearance and Characteristics 

Euonymus is a genus of flowering plants in the staff vine family, Celastraceae. Common names vary widely among different species and between different English-speaking countries, but include spindle (or spindle tree), burning-bush, strawberry-bush, wahoo, wintercreeper, or simply euonymus. It comprises about 130 species of deciduous and evergreen shrubs, small trees and lianas. They are mostly native to East Asia, extending to the Himalayas, and they are also distributed in Europe, Australasia, North America, and Madagascar. 50 species are endemic to China.

The inconspicuous flowers occur in small groups, and can be green, yellow, pink or maroon in color depending on species. The leaves are opposite (rarely alternate) and simple ovoid, typically 2–15 cm long, and usually with a finely serrated margin. The fruit is a pink or white four- or five-valved pod-like berry, which splits open to reveal the fleshy-coated orange or red seeds.

The seeds are eaten by frugivorous birds, which digest the fleshy seed coat and disperse the seeds in their droppings. Many species are used for medicinal use, and parts of the plants can be poisonous to humans.

II. How to Grow and Care

Sunlight and Climate

These plants need to be in USDA Hardiness Zones 4 to 8 in order to thrive.

Also, they need full sun or partial shade exposure. Full shade is tolerable, but growth won’t be optimal.

Watering 

Drainage is essential for Euonymus. This hardy plant cannot handle soggy conditions, leading to root rot. The soil must allow drainage, and container-grown plants must be in a pot with drainage holes. Let the top few inches of soil dry out before giving the plant water. Euonymus is drought-tolerant, but assisting during a dry spell will keep the shrub healthy and thriving. Only water during the growing season and start to scale back during the fall to help prepare the plant for winter.

Fertilizing 

Quality soil with a high organic content can take the place of routine fertilization as this plant is not a heavy feeder. Nevertheless, feeding the plant can help nurture it and allow it to push out more of its striking foliage. Cultivars like Wintercreeper can benefit from applying slow-release fertilizer once per year. Burning Bush varieties prefer to be fed during the spring and again during the middle of the summer to support sustained growth..

Soil

Moist, well-draining, and fertile soil is what’s necessary for Euonymus, so provide soil with a loamy texture and an adequate organic matter content.

These plants do well with a variety of pH levels, so shoot for a range of 6.0 to 8.0.

Pruning 

Euonymus is a plant that benefits from a regular trim, but the extent of the cutting depends on how the plant looks and how you want it to look. Groundcover varieties can be allowed to spread out, but plants with a more manicured, shrub-like appearance can be shaped to have a rounded look. Older plants can be rejuvenated with an aggressive trim. This plant can be invasive in some areas, so some gardeners opt to deadhead to prevent the spread of seed.

Propagation

With many different species comes many ways to propagate. You can propagate Euonymus by sowing seeds, taking cuttings, layering, or transplanting.

• From Seeds

First things first: you need seeds. In autumn, pick ripened Euonymus berries and remove their seeds. Put the harvested seeds into a strainer, rinse, then air dry on a paper towel.

Fill a baggie with moist sand, then bury the seeds within said sand. To stratify the seeds, refrigerate the baggie for at least three months at 40°F. Come next summer, it’ll be sowing time.

When it’s 70 to 85°F outside, sow the seeds a quarter-inch deep in well-draining garden soil, with enough space between them to accommodate for their mature sizes.

Water the seeds upon sowing, and mulch the seed beds with pine straw to keep weeds down while also allowing in sunlight and moisture. Keep the soil moist until the seeds germinate, in about eight weeks.

• From Cuttings

To take stem cuttings from an Euonymus, select healthy semi-hardwood or hardwood stems in summer, or hardwood stems in winter.

Cut three- to four-inch lengths just below a node with a sterilized blade, defoliate the bottom halves, then dip the cut ends into an IBA rooting hormone powder.

Stick the IBA-dipped ends of the cutting into a tray that’s filled with a 50-50 rooting medium of vermiculite and sand. Make sure to keep the medium moist via misting without drenching it.

The cuttings will need to be indirectly lit, and kept at 70 to 85°F.

Once strong root systems have developed, in four to eight weeks or so, you’ll want to start the hardening off process.

Bring the cuttings outside for 30 to 60 minutes one day, and add 30 to 60 additional minutes each day until the cuttings are conditioned to survive a full day outdoors. After that, they’re ready for transplanting.

• Via Layering

My preferred layering method with Euonymus is tip layering, which works especially well with vining species like E. fortunei.

Select a healthy, flexible stem during the summer and make a slanting cut a quarter to half of the way between the tip and where it connects to the mother plant.

Then, stick the tip – still attached to the mother plant – into the adjacent soil, bury it, and keep it affixed with a stone or horticultural staple.

Keep the soil around the layered tip moist until a new shoot grows from it. At this point, congratulations! It’s time for transplanting.

• From Transplants

If you’re transplanting Euonymus, you’ll want to do so in autumn.

Prior to planting, prepare the site with a couple of inches of fresh compost or rotted manure tilled into the soil. Dig a hole slightly wider than and just as deep as the transplant’s root system.

Come transplanting time, lower the plant into the ground. Backfill the gaps in the hole with nearby soil, and water the whole thing in. Keep the planting site well irrigated until the plant becomes established.

Overwintering

Winter care is very minimal for Euonymus. It is generally unnecessary to cover or protect the plants during the winter. These plants are hardy in winter. Some varieties are deciduous and will drop their leaves, while others are broadleaf evergreens and retain their foliage during the winter. Remove dead or damaged growth during the fall, but the plants should be left alone during the winter, and you can resume watering, fertilizing, and pruning in the spring.

Pests and Diseases

Keeping your Euonymus in peak condition will help keep it free of pests and diseases, which tend to afflict unhealthy specimens more so than healthy ones.

Common Pests

Insects tend to vector pathogens, so keeping your plants pest-free will help to keep them disease-free. But with Euonymus, there’s one pest in particular we should watch out for:

• Euonymus Scale

When the pest is named after the plant it infests, you know it’s a problem. Females are brown, stout, and a bit longer than a millimeter, while males are white, elongated, and a bit shorter than a millimeter.

Both nymphs and eggs are small and yellow, the latter of which hatch under the adult females in summer.

Adults and nymphs alike feed on plant sap, which leads to leaf chlorosis. That, plus feeding damage, eventually results in leaf defoliation and branch death. Worst-case scenario, the entire plant dies.

Control measures include removing heavily infested branches and applying chemical insecticides. Imidacloprid, a systemic insecticide, should be applied as a soil drench in autumn.

Horticultural oil or insecticidal soap can be used on nymphs, but they won’t have an effect on the armored adults, so apply them in early June to target the juveniles before they become adults.

Common Disease

In addition to keeping Euonymus free of pests, using sterilized tools and disease-free seeds/mother plants will help keep them safe from pathogens.

• Anthracnose

Caused by the fungus Colletotrichum gloeosporioides, anthracnose results in small, brownish spots with lighter-colored centers on leaf tissues.

Over time, these spots can seriously defoliate Euonymus, especially variegated varieties. Wet and cool springs are a risk factor for anthracnose infection, so keep alert during those chilly April showers.

Pruning infected tissues and destroying infected plant detritus helps to control Anthracnose spread. Copper fungicides applied periodically can be effective as a preventative measure.

• Cercospora Leaf Spot

This disease results in small brown foliar spots that tend to merge and coat entire leaves. As the spots grow, small gray centers often form in the middle of these blotches.

The causal pathogens include Cercospora euonymi, along with Cercospora destructiva, ominously enough.

Cercospora leaf spot rarely results in plant death, so don’t fret. But it often saps away at the aesthetics and vigor of infected plants, so you’ll want to collect and dispose of fallen foliage.

Treat and control already-infected plants with sprays of thiophanate-methyl.

• Crown Gall

Crown gall causes rounded, irregular galls several inches in diameter to pop up throughout the plant, whether on the roots, stems, or at the soil line.

These galls interfere with plant metabolism, resulting in weakened vigor, foliar chlorosis, and branch necrosis. Crown gall is caused by Agrobacterium tumefaciens, which dwells in the soil.

Unfortunately, there’s no cure for diseased plants. They’ll live on for several years, though, so prune infected branches below the galls for improved aesthetics. Destroy any severely diseased plants.

A. tumefaciens spreads via contaminated tools, infected transplants, and diseased soil, so ensure all those blades, Euonymus, and growing mediums are sterilized and/or disease-free.

The bacteria lives on in soil for two to three years, so if you’ve removed an infected plant and want to replace it, do so with crown-gall resistant species such as holly, boxwood, or barberry.

• Scab

The causal fungus for this disease, Elsinoë euonymi-japonici, specifically goes after E. japonicus.

Infected leaves and stems form light-to-dark spots with raised, rust-colored borders. These blemishes often merge together, interfering with photosynthesis and damaging plant tissues.

In Euonymus, you control scab the same way you would Cercospora leaf spot: by disposing of infected plant detritus and applying thiophanate-methyl sprays.

III. Uses and Benefits 

• Ornamental uses

These plants have many uses within the landscape. They can stand out as specimens, or complement other plantings.

Euonymus can look fantastic out in the open, or up against structural foundations. Deciduous species tend to provide spectacular foliar interest in the fall, as well.

Speaking of foliage, Euonymus leaves can be variegated, and shaped in various ways, allowing for ornamental versatility.

Large varieties make for good hedges and screens, while creeping ones work well as ground covers or climbing vines. Additionally, small or dwarf cultivars can fill in visual gaps without taking up too much space.

• Other uses

The wood of some species was traditionally used for the making of spindles for spinning wool; this use is the origin of the British English name of the shrubs.