Gardenias are incredibly prized for their gorgeous, fragrant blooms and glossy, deep green foliage.
Even in their ideal climate, these plants can be finicky and high-maintenance, but gardeners are happy to put in the effort to reap the rewards of this beautiful plant. So what is the gardenia origin?
What Is The Gardenia Plant’s Origin?
Gardenias originated in Asia and have been cultivated in China for over 1,000 years. [1]
How Is The Name Pronounced?
Gardenia is pronounced [gaar-DEE-nee-uh].
Where Did The Name Gardenia Come From?
Gardenia was named by botanist John Ellis in England in 1761 after it had been brought over from the Far East.
What Is The Plant Related To?
Gardenia is actually a member of the coffee plant family and not a member of the jasmine family as the botanical name implies.
How Many Species Of Gardenias Are There?
There are over 200 species of plants in the gardenia family. [2]
What Is The Botanical Name?
The most common gardenia encountered is Gardenia jasminoides, named for its resemblance to jasmine.
What Are The Common Names For Gardenia?
Common names of gardenia are the:
- Cape jasmine
- Cape jessamine, and even just “jasmine,” although it is not a relative of that plant.
Growing The Gardenia
Size and Growth
The wide range of cultivars of Gardenia give rise to many different shapes and growth habits.
Generally speaking, it is grown as a shrub that can reach 2′-8′ feet tall and wide.
Flowering and Fragrance
Gardenias are prized for their large blooms and pleasant, jasmine-like fragrance.
Light and Temperature
Gardenias grow well in USDA hardiness zones 8 – 10, and cold-hardy species can survive winters in USDA hardiness zones 7 and 6b.
They are sensitive to temperature; overnight lows above 60° degrees fahreinhit may cause flower buds to brown and drop off, and overnight lows below 15° degrees may cause severe cold damage.
Watering and Feeding
It is best to use hard water for gardenias, or to even add small amounts of lemon juice or vinegar to the water before watering, in order to ensure that they have the correct pH levels.
For tips on fertilizing read: What Is The Best Gardenia Fertilizer?
Soil and Transplanting
They prefer high humidity and acidic soil, and don’t respond well to being moved, so try to identify the perfect spot for your gardenia before planting it.
If your soil is not acidic enough, it may lead to chlorosis, as the plant cannot absorb enough nutrients from the soil. Consider enriching your soil with acidic materials like coffee grounds.
Grooming
Prune gardenias just after they finish blooming in the summer, in order to not disturb the new flower buds that will set in the fall.
Pruning will help the plant keep its shape, and help prevent it from becoming top-heavy, or forming heavy branches that will break.
How To Propagate A Gardenia
Gardenias propagate readily from cuttings, and, because this plant is so sensitive, it’s a good idea to have a backup.
If you find the ideal conditions for your gardenia, take advantage of the opportunity to start new plants.
Or, if you aren’t sure how your gardenia will survive during the winter, propagate a new one to overwinter indoors just in case. Because gardenias require pruning in mid-summer, it’s a great time to harvest some cuttings for new plants.
To propagate a gardenia, first ensure that the parent plant is healthy. Water it deeply the day before, and look for promising new growth.
Choose stems that are healthy and show no signs of disease, and inspect them carefully before and after cutting to eliminate pests.
- Cut stems that are 4-6 inches long, using a sharp, clean blade. Cut just below the leaf node, at a 45-degree angle.
- Remove leaves near the bottom of the stem, leaving at least two leaves at the growing tip.
- Dip the end of the cutting in root hormone powder.
- Prepare a pot with a mix of moist sand and peat moss.
- Using your finger or a pencil, make a hole two inches deep in your pot.
- Insert the cutting into the pot, being careful not to brush off the hormone powder, and firm the soil into place with your fingers.
- Place a clear plastic bag over the flower pot, but don’t let it rest on the stem of your gardenia. If necessary, use skewers or drinking straws to build a support that lets the plastic bag act as a tent over the plant without resting on it.
- Keep the plastic-covered bag in a warm spot that is about 70-80 degrees, and where it receives several hours a day of indirect sunlight.
- Keep the soil moist by removing the plastic bag and lightly watering or misting every day or two. Removing the bag periodically also allows new air to circulate around the leaves and prevents fungus.
The cutting should root within 4-6 weeks of planting.
Caring For A Gardenia
When growing a gardenia outdoors, plant in an area that receives lots of direct sun, but is sheltered from the hottest, drying afternoon rays. They prefer acidic soil.
The soil should be rich, moist, and well-drained, and should be consistently damp but not soggy. Apply 2-4 inches of mulch to preserve moisture, and provide 1 inch of rain or water a week.
When growing a gardenia indoors, place in a sunny window where it can get 4-8 hours of direct sun daily.
Create a humid environment with a humidifier or pebble tray. While you can mist a gardenia to create humidity and provide moisture, avoid over-misting to discourage fungus growth.
Pests, Diseases, Or Problems Common For The Gardenia
Because gardenias thrive in moist, humid environments, they are prone to attract unhealthy fungus growth. The most common gardenia infections are:
Root Rot
Fungal pathogens destroy the plant’s delicate root tissues, causing the gardenia to wilt and yellow, starting with the oldest leaves first.
If you suspect root rot, you can save the damaged plant by digging it up, pruning away damaged roots, and re-planting in soil with better drainage.
Prevent root rot by choosing well-drained soil and avoiding over-watering.
Powdery Mildew
The humid conditions gardenias prefer can also foster powdery mildew.
Powdery mildew creates a white, fuzzy, powdery coating on the leaves, and weakening and deformation of new growth on the plant.
You can control powdery mildew with neem oil, and prevent it by selectively pruning the gardenia or surrounding plants to provide greater air circulation.
Chlorosis
When growing Gardenia plants sometimes will display yellow leaves due to chlorosis. Applying Epsom salts can help clear up the yellowing.
Tips, Tricks, And Suggestions For Your Gardenia
Here are some tips to get the best flowers on your gardenia.
- Flower buds will form when night temperatures are below 60, and daytime temperatures are above 75
- In order to bloom, the budding plant need several hours of bright, filtered sunlight every day
- Prune your gardenia in the summer, right after it has stopped blooming. New flower buds are set in the fall, so late pruning may inhibit flowering the following year
Buying Tips
No matter what species of gardenia you are shopping for, look for a healthy, vigorous plant with new growth at the tips.
Because gardenias are not fond of being moved repeatedly, it is best to choose the right place for your gardenia before you bring it home.
What Are The Most Popular Gardenia Species And Varieties?
The most popular species of gardenia is Gardenia jasminoides, named after its fragrance.
This cultivar is also known as Gardenia augusta, Gardenia florida, and Gardenia grandiflora.
This shrub will grow from 3′-6′ feet in height, with flowers up to 3″ inches across.
However, gardenia also has many available cultivars, including double-flowered varieties, varieties that bloom a second time in fall, dwarf species, and even Gardenia radicans which can be used as a ground cover.
Summary
Gardenias are famous for their magnificent, creamy white, fragrant blossoms set against lustrous glossy foliage.
When you find the magical combination of light, moisture, temperature, and humidity for a gardenia to thrive, there is simply no substitute for this incredible flower.