Bougainvillea is a hardy plant, but the cold winter’s frost will destroy it.
If you want to preserve and save your bougainvillea for next season, there are steps you can take to overwinter it.
Originating from South America, this popular garden plant has over 300 types. They’re known as perennial evergreens and grown for their bright bracts, heart shaped leaves, and thorny nature.
This flowering shrub is super hardy to bugs, heat, and even some drought when established. But not the cold. Bougies will get wrecked by the harshness of it.
So it’s relying on YOU to save it.
Protecting it from the cold is a crucial step. And you must do it before the temperatures start to dip in the fall because it can be too late.
Depending on the size of your bougainvillea, whether it’s potted or not, and your local climate, it can be a breeze to get these guys safe from the cold.
Or it can be a nightmare if yours is already established so it’s just unwieldy.
Let’s winterize your bougainvillea with this detailed guide. If you still have questions after reading it, post a comment so I can get back to you with my thoughts.
If you don’t do it right your bougies will suffer. It can drop leaves, and petals, or even fail to bloom.
You don’t want that, right?
Read on to get the details to keep your plants safe from the winter. And find out how to bring it back to the outdoors in the spring.
Guide Contents
When to overwinter bougainvillea
As you probably know, paperplants are perennials by nature. They’re not one trick ponies that only show off those gorgeous pink petals just to vanish.
They come back every year if the conditions provide.
Bougainvillea is a blooming vine plant that is well tolerant of heat, pests, and even the cold once they get some strength. Younger plants are more vulnerable.
But established ones can handle some degree of cold.
Regardless of the plant’s age, they don’t like the cold. Bougies aren’t cold hardy. They don’t do well in the cold during the fall and into the winter, so that’s why you need to protect them!
Bougainvillea blooms are almost nonstop in warmer regions. For those in these zones, you have nothing to worry about other than some basic mulching or plant wrapping.
But for northern gardeners, you’ll have to do a bit more work to keep it well during the cold.
These plants will show signs of damage when the outside air gets to around 40F but can tolerate dips to 30F when they become established.
Winter care ensures a happy plant that produces plenty of bright flowers next season with those pretty bracts.
For those growing in zones 9-12, you don’t have to worry too much about it. It can handle a light freeze but deep ones will damage the root system.
But for those growing these plants in cooler zones, you’ll have to do some work. These plants should be grown in containers and then moved into the shelter, whether that’s inside your garage, house, or shed.
Warmer zones in the south like Texas can have hot summers, but very cold winters. So don’t assume your bougie will be fine.
So if you’re in zones 9 or higher, the temperatures aren’t cool enough to damage bougies in the winter.
But still, watch out for cold snaps that came outta nowhere. Watch the weather and prepare to take action when necessary.
Some light to moderate inches of mulch on the root system will suffice. In areas where harsh weather is present in the cooler season, there are some things to make it easier on yourself.
In northern zones, winter prep should be done ahead of time before the frost.
When the temperatures in the soil dip to 32F, your bougainvillea is in danger. The air temperatures don’t matter as much as the soil temperature, but you can use them as a gauge. When the ambient temperature dips to 40F, then you need to start winterizing.
Giving yourself time will be less of a rush for last-minute changes and gives your bougie plenty of time to adjust. If you just toss it right it can cause plant shock.
Thankfully, most people do grow them as container plants. Their shrublike appearance gives them heights upwards of 20 feet tall. You can guess that some pruning is involved.
When to start winterizing
The way to do it is to check your local temperature! It’ll tell you exactly when to overwinter.
When the temperatures approach 50F, it’s a reasonable time to start. It gives your plant more time to adjust.
- For younger plants that are 1-2 years old, you should winterize earlier in the season (temperatures around 50F.
- For older ones, you have more leeway because of their cold tolerance (temperatures around 40F).
Wherever you’re located, you need to take action before the cold comes in.
Once fall comes and it gets cooler, it can severely damage your plant. But if it’s only been a few days or so with minimal cold exposure, you may only see slight browning, leaf drop, or wilting.
These can be fixed if you move your plant to safety for the rest of the winter.
What happens to bougainvillea in winter?
It depends on where you are.
For warmer zones, like California, Arizona, or New Mexico, the plant will enter a state of semi-dormancy. It won’t grow and won’t produce flowers, but it’s not fully dormant.
In cooler zones, such as Texas or some parts of Florida (Key West), it can get pretty cold so it’ll enter full dormancy. In temperate zones, it’ll likely stay evergreen all season. Cool huh?
Prune it back
Cutting it back is necessary to help it shed those extra leaves.
It’s going to drop them anyway, but if you prune it back before the winter season, it reduces the risk of pests or pathogens infesting the wilting bougie.
How do you trim bougainvillea for winter?
Cut it back to help make it easier to handle. It saves space and the leaves will be dropped.
When they begin to brown, remove them from the cane.
If you decide to wait, you can prune when the leaves drop. Cutting back will be necessary for cooler zones. Get a clean pair of pruners then sterilize them with some rubbing alcohol.
Put on some protective gloves so you don’t get caught in the thorns.
Prune the canes back to reduce the size of the plant so it’s more manageable. It makes it easier to wrap in plant cover or move around if needed. Remove dead leaves, branches, or spent flowers. These can be completely pruned off as they’re not going to help during the winter.
There’s no need to prune it down to the soil level. Just cut the canes to the next node in line. It should be bulging at the joint.
Nyctaginaceae will survive the winter if it’s pruned and protected from the climate even if severely cut back, so don’t worry too much about it.
Winter pruning helps get you more blooms next spring so it’s a good thing!
In warmer zones, pruning may not be necessary. If your plant doesn’t fully enter dormancy, it’ll need some leaves to sustain itself.
You can still prune, but don’t cut it back as much.
Cut back the canes that stem from the primary trunk. Dormant species will grow back in the spring. But semi-dormant species may be harmed if pruned too far.
Bougainvillea dormancy
Bougainvillea will enter dormancy when winter approaches.
The plant will go to “sleep” to conserve its stock of nutrients in the roots. This is what the plant feeds itself with during the cold season and sustains itself.
The leaves will fall off on their own and the plant will die back. The reason for the leaf drop is that it knows there’s very little photoperiod (light) in the winter, so it drops them because it doesn’t need to photosynthesize.
With fewer leaves, it has less to feed.
During dormancy, reduce watering and stop fertilizing. Gradually reduce the water over time at the end of summer. The soil should be allowed to become less saturated with water. The key is to not rush.
You may be questioning whether or not your bougainvillea has died during this time.
You can test it by doing a scratch test- scraping a piece of the bark. Look for some green or yellow under the branch bark. The tips or outer layer may be damaged, but the inside is still good.
Dormancy doesn’t always occur. If it doesn’t, avoid hard pruning. This is common in areas that are warmer in the winter.
How to overwinter bougainvillea
This part of the guide includes some general tips you can utilize to make your winterizing a success.
Again, depending on your location, your needs will vary.
Supplement with mulch
Add a 3-5” thick layer of organic mulch over the root system to help insulate it from the cold.
You can use hay, straw, leaf litter, or just plain old wooden mulch. This will help keep bugs out, protect them from cold, and give the plant some nutrients to grow in the springtime.
If you’re planting in a warmer, more temperate zone, you may be able to get away with just putting a layer of it. It can also come in handy when cold snaps take place for some quick protection.
Mulch also helps retain moisture, so you can water less throughout the onset of winter.
Use plant wraps
Wrapping your plant can provide some protection from sudden temperature changes, bugs, and even scorching sunlight.
There are dozens of covers and wraps on the market available in various sizes and materials.
Avoid using plastic. While cheap, it can trap humidity which can increase humidity.
It also provides little protection from the cold. Look into using other materials like Velcro, burlap, or wool.
You want the wrap to be thick, effective, and offer good protection from frost and cold weather.
If it’s advertised to insulate seedlings or younger plants from the cold, then you’re on a good track.
Younger bougainvillea that are only a few feet tall can be covered with floating row covers.
These need to be staked so they don’t get blown away by the wind. Larger bougies can be covered with polypropylene which allows air and UV light exchange.
They’re an economical solution because they’re cheap, reusable, plus offer protection down to 25F on average. You can leave them on your plants during the whole season. The wraps can be removed when springtime comes.
Or you can put them on if cold snaps break out or during cooler temps. In regions where it’s expected to be frosty outside for a few days or more, wraps may not be sufficient.
You’ll have to move your paper plant indoors or into a temperature-controlled greenhouse combined with wrapping.
Larger bougies are harder to wrap, but you don’t need to wrap the whole plant!
The roots are what’s important, not the canes or leaves. Use a thick layer of mulch to help protect the root system at the base of the plant.
If the roots get too cold, the whole thing will die. So don’t let that happen to your precious plant!
You can wrap the upper portion of the plant with wrap, but use a 3-4 inch layer of organic mulch for the root system. Hay, straw, leaf litter, or compost can be used. Avoid touching the actual trunk with it though.
Remove the mulch in the spring when the temperatures rise. You can also use sheets, blankets, or freeze cloth for plants. Don’t let your creativity get limited to commercial products!
On warmer days, remove the wrap if yours is made from materials that don’t allow an exchange of oxygen or release trapped heat. This will allow the heat to escape. Too much heat trapped in there is just as bad.
The humidity will also be a problem if you’re using something like plastic. Humidity will lead to rot, so regularly removing the cover and letting it vent is good practice.
Since these covers can be used with potted bougainvillea, you can help insulate it. Bring it inside your garage or house for the winter and then put a cover over it
Choose a smaller variety
Choosing a dwarf variety of bougainvillea will make it a lot easier to move it around.
When the plant is young, you can move it into the household or shelter with minimal effort. When the temperature dips, you can bring it indoors when needed.
Choosing a smaller plant that can flourish in a container is ideal for easy transport. Bougie hybrids are also a good choice.
Some dwarf varieties that are good for container planting include:
- Helen Johnson
- Sunvillea Rose
- Sunvillea Cream
- Pink Pixie
- Orange King
- Oransenka
- Baby Mia
- B. glabra
- Bambionos
- Barbara Karst
- La Jolla
- Crimson Jewel
- Oo-La-La
Grow in a container
Bougainvillea grown in a pot provides ample benefits compared to soil-sown plants. Container-grown bougies are much easier to move around, which makes overwintering less of a pain.
But they do come with their own drawbacks as well.
Generally, plants in pots will have less thermal insulation compared to soil-grown plants because the pot is exposed to the day/night cycle.
This makes the material lose heat much more quickly compared to the soil. Of course, the material, size, and location will make a difference.
lastic will be more sensitive to temp swings compared to terra cotta, for example. Larger pots will hold heat more efficiently than smaller pots. And so on.
When choosing a pot to use, get something that’s porous and retains heat well. It should also accommodate your plant’s root system and be light enough to move around.
Consider using a plant roller so you can just push it around so you don’t break your back. Combining a dwarf variety with a well-insulated pot would be ideal for winterizing.
Choose a site that has easy access indoors.
If you’re growing it as a patio plant on the balcony, this is ideal because you can easily sneak it inside your home if needed.
Patios, porches, or balconies are good placements. When the weather gets cool, just bring it inside into a sunny spot until spring.
The container should be a couple of inches larger than the plant’s root ball. The plant grows in dry soil natively, but you should keep it moist to help insulate the temperature from affecting the soil.
If the pot is too small, it can restrict the roots. Using rich, organic, well-draining soil if possible.
Note that bougainvillea will become stressed when you uproot it, so using a pot from the start is ideal. This way, you don’t risk damaging the roots.
How to winterize in containers
Plants in zones 8 or lower generally will need to be brought into the shelter. Zone 9 is hit or miss. You’ll likely have to bring it inside anyway, so you may as well prepare for it.
The exception is if your area never drops to the 40-50F degree range.
You may be able to keep it out if the place you’re keeping it is safe from the cold. Some people create microclimates in their gardens to accomplish this.
Bring it inside before the first frost because containers won’t provide ample protection. The soil insulates the most efficiently. Containers are raised, so they don’t retain heat as well as the soil because it just dissipates.
Find a good spot that gets winter sun exposure to keep it warm and dry.
Bright, filtered light is ideal. Some direct light in the morning is also good.
Keeping temperatures at room temp (72F) is okay, but it should have some degree of cold exposure so it stays dormant. Try to aim for a range between 50-60F.
Ensure that there are no winds, drafts, or highly trafficked areas. Garages, sheds, or greenhouses are good choices to overwinter bougies.
When bringing it inside, the plant will be stressed. One of the biggest mistakes that newbie gardeners make is moving it in and then out without acclimation.
Or plant it in the soil and then move it into a pot. It hates being uprooted once it’s established.
Check for signs of plant viruses, pests, or other nasties before you bring it in. Neem oil can help reduce the occurrence of pests or fungal issues but must be used with care.
Read the directions and keep pets/people away. It must be applied out of the direct sun and excess oil should be washed off.
But once you apply it, you can have peace of mind because neem has a residual effect.
Choose a location that has a stable temp above 50F, is free from winds or drafts, and gets ambient sunlight in the daytime.
Once you’ve decided, drench the soil. This helps insulate the roots from swings.
Wet soil provides superior insulation over dry soil. Put a layer of 3” mulch over the root system. Organic mulch can also feed your plant during winterization.
Next, wrap your plant using a plant cover or blanket. If temperatures are expected to dip below 45F, use thicker or multiple layers.
Don’t use plastic or bubble wrap. Secure the plant material so it doesn’t blow away or become loose. This will prevent the cold from getting in.
Depending on where you’re located, gardeners that don’t face tremendously cold winters can get wavy with leaving their bougainvillea outside. Wrapped up of course. Find somewhere that’s free from the winds.
Keep the soil moist, but not wet. Ensure that the plant won’t topple.
You may need to put in some plant supports so it doesn’t fall over when it’s wrapped. Note that the pot should be wrapped, not the entire plant!
For cooler zones, you’ll have to move it indoors combined with some plant wrap. When the temperatures dip to the lower 40s, it should already be safely nestled inside your house.
Prune it back when it’s fully dormant and then move it inside. If it’s semi-dormant, move it to a protected area with minimal pruning. Don’t fully prune unless it’s fully dormant.
You can store bougainvillea in the garage, shed, or greenhouse to prevent the cold from getting to it, but not completely end its dormancy
Some cold exposure is necessary so it can enter dormancy, but not too much!
During the winter, check the water level every 2 weeks. Water it to get it moist, but nothing more. It should never be fully dried out between watering sessions. Light can help offer some warmth, but it’s not necessary during overwintering.
Ensuring that average moisture is received by your plant in dormancy will help it thrive. You can also prune heavily in its dormant state.
Do NOT prune when it’s active or semi-dormant if possible!
If you prune when it’s dormant, it’ll respond by rewarding you with dense growth and colorful flower bracts in the springtime.
You should be doing most of the pruning during dormancy and little to none during the summer/spring.
How to care for bougainvillea during the winter
There’s not much to do during this time. Your plant is resting, so let it be.
It needs minimal care and some people even push pruning until the evening temperatures stabilize above 40F. But some will prune now because it’s dormant.
It’s recharging for next season to bring you those gorgeous blooms once again. There are only a few things you need to do when it’s overwintering:
First, only water when the soil is barely dried out. I’ve mentioned this multiple times in this post, but it’s because it’s pretty darn important.
Some people don’t need water at all during this time.
The plant covers help keep the water from evaporating too quickly. You may even get away with watering once every other month or so.
Water deeply and sparingly rather than frequently and shell only.
Winter care for potted plants involves more watering than garden-sown ones.
To ensure that your plant gets the water it needs, use high-quality soil that has a good mix and allows for superb drainage. There should be multiple holes in the pot you use as well.
This doesn’t mean let it dry out but only barely. Use a soil meter if you don’t know when to water. This will give you soil specifics so you can water appropriately.
Generally, you’ll water about once or twice per month for winterized bougainvillea. If you overdo it, the water won’t be used so it’ll just collect at the base of the plant. This brings pests or plant pathogens like root rot.
For warmer days where temperatures rise above 65F, you’ll want to remove the wraps to let it vent. Moisture or heat buildup will be an issue.
Placing it somewhere sunny is ideal with full sun in the morning and then dipping in the afternoon.
It doesn’t need a bunch of light during this time, but some wi