Euonymus Winter Care: Tips On Preventing Winter Damage To Euonymus
The Golden Euonymous is one of the most popular species in the genus. They are native to North America from Canada southward into Mexico and Central America.
They have been introduced to other countries such as Australia, New Zealand, South Africa, and Argentina. There are two subspecies of golden euonymous; one is found in northern temperate climates (e.g. United States) and the other is found in southern temperate climates (e.g. Brazil). These two subspecies differ mainly in their leaf coloration, which varies from yellowish green to brown or even black.
Golden euonymous are usually considered “winter” plants because they tend to drop their leaves during winter months when temperatures fall below freezing. However, there are many reasons why golden euonymous may not drop their leaves completely.
Some of these reasons include:
Winter is a time when euonymus needs extra protection from cold weather conditions. This means that it’s best to keep your golden euonymous protected from extreme cold by placing them indoors during the winter months.
If you live in a warm climate where winters are milder than those in the northeastern U.S. for example, then you can leave your euonymus outside (but keep an eye on them for signs of damage). If you live somewhere with extremely cold winters such as those in the northern U.S. or Canada, it’s best to bring your plants inside (and place them where there is plenty of light).
Golden euonymous drop their leaves during the winter because it is a survival mechanism. When the days become shorter and nights become longer, euonymus plants realize that they aren’t going to receive as much sunlight as they do during the summer months.
In response, they begin withdrawing nutrients from their leaves in order to sustain essential functions of the plant (such as root growth). As a result, golden euonymous drop their leaves during winter.
The illustration above shows a healthy golden euonymous. During the winter months (or any time their leaves drop), you may find that your euonymus plants look like the one on the right.
Don’t worry; this is completely natural.
It’s been my experience that golden euonymous produce tiny yellow flowers during spring and summer months. However, it should be noted that some golden euonymous varieties do not produce flowers at all.
So if you’re hoping to enjoy the beauty of yellow flowers, you may be disappointed.
In case you’re wondering, golden euonymus is classified as an “evergreen” plant because it holds onto its leaves year-round. Technically speaking, a true evergreen would be a plant that holds onto its leaves for more than just one season of the year.
More Winter Care Tips For Golden Euonymus:
Be sure to water your euonymus thoroughly right before the onset of cold weather conditions. In other words, water them heavily right before the first frost is expected in your area.
Why water them heavily at this time?
The idea is to force your plant to “harden off” prior to the cold weather. This means exposing it gradually to colder temperatures in order to increase its tolerance to low-temperature conditions.
The size of your plant (and the amount of soil it is planted in) will determine how many times you need to water it per year. During the first year after you’ve planted your euonymus, you’ll need to water it at least twice per season (more often if rainfall is lacking).
As your plant grows, it will require less watering. General rule of thumb: water your plant well if the soil is dry to a depth of 1 foot.
An easy way to water your euonymus (and other potted plants) is to place it in a shallow pan (such as a baking pan) and then fill the pan with water until it overflows and floods the pot. Then just let the soil soak up as much water as it can.
This works well for non-porous soil types such as clay. Just don’t leave the plant sitting in water for more than a week because this could cause root rot.
Golden euonymus tend to grow much faster under bright artificial light (such as that of a grow light) than those that experience natural lighting conditions. If possible, place your plant within 3 feet of a fluorescent tube (of at least 40 watts).
For best results, place the entire pot (with soil and all) under the grow light. Move it gradually closer to the light every couple of days in order to harden it off. Once per week, spread a thin layer of fast-drying fertilizer around the top of the soil.
A note about watering euonymus and other plants grown in containers: Contrary to popular belief, most plants DO need to be watered on a regular basis. Many people make the mistake of waiting until the soil is completely dry before watering.
This is bad for several reasons:
1) It’s bad for your plant.
2) It’s bad for the environment.
3) It’s much more expensive due to excessive water usage.
Here are some quick rules of thumb for watering your plants:
1) Water them well right before they go into dormancy (usually during winter).
This means that the soil should be wet at a depth of at least one foot.
2) Allow the top 2 inches of soil to dry out before watering (during the times when they aren’t dormant).
3) Water thoroughly but don’t waste water by drowning your plants.
The best time to repot your euonymus is during the spring, once it’s finished blooming. Most gardeners recommend that you should only repot an euonymus when the soil is starting to break down or become very weak and crumbly.
This happens once per year. If repotting isn’t necessary, then don’t bother!
In order to repot your euonymus, follow these simple instructions:
1) Hold the plant at the top by the stem (do not grab near the base of the trunk).
2) Carefully lift it out of the pot.
3) Check to see if the root mass has broken through the original pot.
If so, trim away any dead roots with a sharp tool.
4) Place the plant into a new pot that is one size larger.
5) Add fresh soil to fill in any empty space in the bottom of the pot.
6) Gently firm the soil around the root mass and water it well.
If your plant has not broken through the original pot, then just place it into a larger pot. When you place it into a new container, your goal should be to cover no more than about 1/3 of the root mass with soil.
You should still leave plenty of space around the trunk for air to circulate (of course, it’s okay if the root mass goes beyond the edge of the pot). After placing it in a new container, firm the soil well and water it well.
Once you have repotted your plant, place it in a location with bright light (such as a windowsill) and withhold from watering for 3 weeks. Once the 3 weeks have passed, water it well and place it back in its normal location.
As for fertilizer, if your plant was in a small container, add slow-release fertilizer according to the packaging instructions. If your plant was in a large container, then fertilize it once per month using a water-soluble fertilizer.
Note: As with all plants that have a tendency to produce large amounts of foliage, euonymus can become susceptible to pests such as spider mites and mealy bugs. Mealy bugs look like little white flakes clustered on the surface of the plant’s stems or around the base of its leaves (these are best seen under a strong light or illuminated with a black light).
Spider mites look like tiny spiders that are web-covered. Consult your local garden center for an insecticide or ask for recommendations.
Good luck with your euonymus!
* Euonymus japonicus is a common species of euonymus that is very popular among bonsai artists. It can reach a mature height of five feet and tolerates trimming well.
It has oval-shaped leaves that are slightly serrated and display pretty shades of reds, golds, oranges, and yellows (varying with climate and time of year). It produces small flowers that, depending on the species, are either red or purple.
* Euonymus alatus (commonly known as the winged euonymus) is an erect shrub native to eastern Asia. This type of euonymus can grow up to twenty feet and tolerates trimming well.
It displays oval-shaped leaves that may be grayish-green or glossy green in color. It is commonly grown for bonsai because of its tolerance for trimming.
* Euonymus alatavicus (commonly known as the lace leaf euonymus) is a large deciduous shrub or small tree that can reach heights of over twenty feet. Its oval-shaped leaves are green in color and display a feathery appearance.
It commonly grows in zones 5-9.
Sources & references used in this article:
Seed dynamics of the liana Euonymus fortunei (Celastraceae) and implications for invasibility1 by TJ Rounsaville, CC Baskin, EA Roualdes… – The Journal of the …, 2018 – BioOne
Recovery of forest floor diversity after removal of the nonnative, invasive plant Euonymus fortunei1 by KZ Mattingly, RW McEwan, RD Paratley… – The Journal of the …, 2016 – BioOne
Winter Damage of Ornamentals by AS Beecher – 1977 – vtechworks.lib.vt.edu