by johnah on February 23, 2021
Gardenia Winter Care – Tips For Wintering Over Gardenia Plants
The following are some tips for winterizing your gardenias:
1) Choose a cold climate area where you live.
If you live in Florida or New York City, then it will not hurt to plant them there. However, if you want to grow them outside in the coldest part of your house, then they won’t do well.
2) Do not use plastic pots.
They will freeze solid in the cold weather. Use glass or ceramic pots instead. Plastic containers may break down during winter time and cause damage to the plants.
3) Keep your gardenias indoors when it gets colder than -10°F (-23°C).
You don’t need to keep them out in the cold either, but they will die if left outdoors all year round.
4) Make sure you have plenty of light in your home.
Gardenias love bright sunlight and will thrive better under it. Also make sure you provide enough water to the plants every day. A little bit goes a long way!
5) Don’t forget to fertilize your gardenias regularly.
Fertilizer helps the soil stay healthy and prevents fungus from developing in the roots of the plant.
6) You can move your gardenias outdoors during the summer and put them back in winter.
They are better off if you keep them in a cool basement room. A cellar would be best, but not everyone has that option.
7) Be careful moving plants outside in the middle of the summer.
If the temperature is too hot, you will burn your plants! The leaves might seem OK, but they can get sunburned just like you can.
8) Don’t leave your gardenia out in the hot sun.
They may need sunlight, but they can easily get burned. If they do get burned, then the gardenia will turn brown and will never bloom again. This doesn’t happen over night, so watch your gardenias for any signs of burning.
Another way to tell if your gardenia is getting too much sun is if the flowers start to look strange or different from its normal appearance.
Gardenia growing zone map
What is the lowest temperature a gardenia can handle?
The minimum temperature that a gardenia can handle without winter protection is -5°C (23°F). The minimum temperature in the winter in the US climate zones 5 through 9, which cover most of the US, is usually far too low to grow gardenias outdoors. Even if they manage to survive outside at those temperatures, their growth will surely be stunted.
How to grow gardenias in containers
Gardenias make excellent container plants. They enjoy being grown in large containers where they can spread their roots out. That doesn’t mean you need to put them in a large pot, but for the health of the plant, they do need adequate room to grow.
A common misconception about a gardenia is that it needs root space equal to the size of its canopy. While this is true for other plants, it is not the case for gardenias.
The soil that you plant your gardenia in should be a light, porous and well-draining mix. You can also use a combination of potting soil mixed with extra perlite or vermiculite to help improve the soil’s ability to drain.
Make sure you water your gardenia regularly, but do not overwater. Gardenias need moist soil, but not wet soil. You can even let the soil dry out a little before watering again.
Overwatering is a common cause of gardenia death.
A good tip to keep in mind when planting a gardenia is to add a 1/4 bleach to a gallon of water to sanitize your pruning tools. This will prevent transfer of disease and fungus from plant to plant.
How to propagate gardenias
Propagating gardenias is actually pretty easy. You can either take softwood cuttings or hardwood cuttings. Softwood cuttings are taken from new growth and are easier than taking a hardwood cutting, plus the success rate is higher.
The best time to take cuttings is in the early spring. In most places this would be March through May.
Choose healthy, younger plants that are about a foot tall. You can also take cuttings from the tips of larger shrubs, but you might have less success. Cut away all of the leaves except for the top ones and remove any flowers or berries from the stem.
Cut the stem at an angle so that there is a flat surface.
Fill your container with a mix of half potting soil and half perlite. Insert the cutting about an inch into the mixture. Fold the top leaves inward over the stem and tuck them under the mixture to hold them in place.
Keep the cuttings in a shaded area and keep the soil moist, but not soaking wet. Mist the leaves regularly to increase the humidity.
You can pot up your new gardenias as soon as you see new growth.
How long does a gardenia take to bloom?
A gardenia can take anywhere from three to five years to bloom. It all depends on the age of the plant and how big it is when you first get it. If you buy a gardenia as a cutting, that can take even longer. After your gardenia blooms, it will likely go dormant during the winter. This is completely normal and nothing to worry about. Just be sure to keep it well-watered during this time.
How to care for a gardenia
When caring for a gardenia, the most important thing is the location. Gardenias need to be planted in an area that receives partial shade throughout the day. They can’t receive full sun or they will burn and die.
The soil your gardenia is planted in needs to be loose, fertile and well-draining. You can plant your gardenia in potting soil or a mixture of potting soil and peat moss.
Gardenias are prone to several different types of fungus and diseases, so it’s important to keep your gardenias healthy by being vigilant about watering and giving them the right environment. Fungus and disease usually occur due to poor environment or watering habits. There are also several pests, such as scale insects and aphids, that can damage or kill your gardenia.
How to prune gardenias
Your gardenia needs to be pruned during the winter or early spring. Pruning helps your gardenia stay healthy and can increase the number of blooms it produces.
First, trim any dead or diseased branches. For woody plants, you want to cut back to where there are fresh green buds. For soft-stemmed gardenias, you can cut back to where there are growing points.
Next, cut back the plant to within two or three buds of the height that you want it to be. This will encourage your gardenia to branch and fill out. Be sure not to prune all the growth away, as this can stress your gardenia.
Finally, apply a thin layer of mulch over the root zone to preserve moisture and keep weeds from growing. Mulch also protects the roots and root zone from extreme temperature fluctuations.
How to propagate gardenias
Gardenias can be propagated through stem cuttings, division, or seed. To propagate a gardenia through stem cuttings, take a cutting from an established plant. The cutting needs to contain at least two sets of leaves.
Dip the cutting in a rooting hormone then insert it into a container filled with moist potting soil. Cover the soil and cutting with a plastic bag to increase humidity and keep the soil moist. If using a misting bottle, set it to mist twice a day.
To divide a gardenia, dig up the plant and trim away any dead or dying roots. Separate the plant into smaller clumps then replant in a new container.
To grow gardenias from seed, gather the seeds when the flower dies back. Spread the seeds out onto a tray and let them dry for a week or two. Then, plant them in moist potting soil.
Keep the soil lightly moist and keep it covered. When seedlings are large enough to handle, transplant them to individual containers.
Sources & references used in this article:
Bulbs in the Basement, Geraniums on the Windowsill: How to Grow & Overwinter 165 Tender Plants by A McGowan, B McGowan – 2012 – books.google.com
Innovations and the nursery industry by B McGowan, A McGowan – 2014 – Storey Publishing
Host plant influence on glassy-winged sharpshooter and its natural enemies by CE Whitcomb – Journal of Environmental Horticulture, 1985 – meridian.allenpress.com
TEMPERATURE REGIMES UNDER ROW COVERS IN OVERWINTER ONION TRANSPLANT PRODUCTION by K Daane, MW Johnson, T Ruiz… – … on Biol. Cont., Berkeley …, 2004 – researchgate.net
Studies on the frost-hardiness of woody plants; 1. The causal relation between sugar content and frost-hardiness by M Rose, P Debach – Israel Journal of Entomology, 1992
Whitefly-plant relationships: behavioural and ecological aspects by DA Bender – HortScience, 1990 – journals.ashs.org
Begonia plant named ‘YAMOUR’ by A Sakai – Contributions from the Institute of Low …, 1962 – eprints.lib.hokudai.ac.jp
Role of calcium in plant responses to stresses: linking basic research to the solution of practical problems by JC Van Lenteren, L Noldus – Whiteflies: their bionomics, pest …, 1990 – researchgate.net