Rose of Sharon (Hibiscus syriacus) is a flowering plant native to parts of East Asia. Although called Rose of Sharon, it is not a rose. Instead, it is a shrub that is a member of the mallow family, related to the tropical hibiscus. It is also known as the shrub Althea, Chinese hibiscus, Korean rose, and hardy hibiscus.
Besides having multiple names, it also comes in multiple color variations, with each one having unique physical attributes. In addition to varying colors, shapes, and sizes, some grow as one large flower, while others bloom in doubles. Its uniqueness makes it a popular choice for indoor gardens.
Rose of Sharon Varieties
Rose of Sharon generally blooms throughout summer, although you can expect its blooming season to differ depending on your location.
Before acquiring a Rose of Sharon for your home, take note that these plants have many varieties. Besides colors, many may grow up to 12 feet tall. Smaller varieties — referred to as mallows or dwarf varieties — grow to a maximum of 4 feet.
Here is information on some Rose of Sharon varieties to help you choose which type suits your home best.
White Chiffon
Just as its name suggests, the White Chiffon Rose of Sharon blooms a pure white. They can reflect moonlight, making them perfect for those growing moon gardens.
White Chiffon flowers are about 4” to 5” in size. The entirety of this plant can grow up to 12 feet tall and 10 feet wide. Its towering height makes it ideal for a terrace, porch, or veranda where they can grow to their full height.
Blue Satin Rose of Sharon
The Blue Satin is also known as the Azurri Blue Satin. It has purplish-blue petals with a deep violet center and bright yellow stamen. Blue Satin was the first Rose of Sharon variety developed to produce no seeds, thereby requiring propagation through cuttings.
Like the White Chiffon, it grows to a maximum height of 12 feet and can spread out to 10 feet.
Blue Chiffon
The Blue Chiffon variety produces large blue-purple flowers with a magenta center. Bunched up in the middle of its five broad petals are many thin, ribbon-like petals surrounding its pale stamen. The Blue Chiffon’s already sizable flowers can be pruned to produce even bigger blooms.
This variety also grows around 8 to 12 feet high, with a maximum width of 10 feet.
Lil Kim
Not all Roses of Sharon are enormous. The Lil Kim, considered a “dwarf” variety, is perfect for people without large outdoor spaces. This smaller shrub only grows to a maximum of 4 feet, both in height and width.
It typically blooms 2 to 3 inch, white flowers with a striking magenta throat. However, there are also Lil Kim plants that produce plum-colored petals.
Purple Pillar
A good variety for an unroofed balcony or terrace with minimal square footage is the Purple Pillar. While it can reach a staggering 16 feet, it only grows to a narrow width of 2 to 3 feet. Its height, though, can be easily managed through regular pruning.
The Purple Pillar has large and vibrant, almost shocking purple and magenta petals. When placed beside each other, this variety makes for a stunning privacy screen.
Pollypetite Rose of Sharon
A newly developed hybrid, the Pollypetite is another dwarf Rose of Sharon, growing to 4 feet high at full maturity. It does not spread wider than 3 to 4 feet and does not require pruning to keep its contained size.
The Pollypetite produces a minuscule amount of viable seeds, perfect for gardeners who don’t want unnecessary spreading and growth.
Its petals are a powdery lilac hue with pale yellow stamen.
Lavender Chiffon
The Lavender Chiffon is a mesmerizing variety with its semi-double flowers that make it look more rose-like. It produces very little to no seeds, making it a non-invasive Rose of Sharon variety. Its flowers also bloom for a very long time.
It stands upright, growing up to 12 feet tall when fully mature. These attributes make it an excellent variety to prune into a tree-like shape.
Minerva
The Minerva’s flowers are similar to the Purple Pillar. It has lavender petals with a slight shock of red in its center, like a ruby halo surrounding its stamen. This variety does not produce many seeds but can easily propagate with cuttings.
Like most Rose of Sharon varieties, this shrub grows tall and wide, making it an attractive hedge or tree. But, it requires some pruning to contain your desired shape. Pruning will also help it produce larger blooms for the next growing season.
Planting Rose of Sharon Indoors
These plants, while native to East Asia, have been cultivated worldwide. You can easily acquire seeds through nurseries and online sellers.
While many varieties mentioned will grow to great heights, there are smaller varieties of Rose of Sharon, which are perfect for indoor gardening.
When growing Roses of Sharon indoors, know that these plants also need some outside time, mainly during summer and spring. They shouldn’t be kept indoors throughout the year, as hibiscus plants need outside air and sunlight to flourish.
It’s best to plant them in spring or fall — or whenever there is no danger of frost. One of the best things about Roses of Sharon is they can do well in urban environments. They can prove hardy against pollution as long as there is good ventilation.
For the best chance of growing lush Roses of Sharon in your home, follow these basic guidelines.
Light Requirements for Rose of Sharon
The Rose of Sharon needs a minimum of four hours of direct sunlight to produce its best flowers. South-facing windows are its most ideal indoor placement. These plants are prone to fungal infestations when kept in shaded areas.
For homes that don’t receive much natural light, consider installing fluorescent lights to give your plant its needed light.
During seasonal transitions from cold to hot and vice versa, give your Rose of Sharon enough time to acclimate. This time is essential to prevent stressing and shocking your plant with direct sunlight. Do this by gradually exposing your plant to less or more sun, depending on the seasonal shift.
Soil and Container
Roses of Sharon are hardy and are not picky when it comes to soil. They can grow planted in poor soil, sand, clay, and loam. However, they are happiest in well-draining, nutrient-rich soil with some mulch for moisture retention.
They aren’t particular about pH levels and can do well anywhere within the range of 5.5 to 7.5.
While these plants are usually planted outdoors in the ground due to their size, they also fare well contained. Make sure to choose pots big enough for future root expansion with a sound drainage system.
Temperature and Humidity
Unlike tropical hibiscus, the Rose of Sharon can withstand cold temperatures, surviving conditions as cold as -20 degrees Fahrenheit. Still, to produce the best blooms, keep it in rooms that are a moderate 60 degrees Fahrenheit. This temperature will also help decrease its water intake and prevent any insect infestations.
This plant can also take the summer heat. However, constant exposure to temperatures over 90 degrees Fahrenheit can cause its buds to drop.
While not particularly picky about humidity, too dry conditions may also cause its buds to fall off. Low humidity can also cause yellowing leaves and encourage insects to swarm. Consider using a humidifier or a humidity tray to combat dry air.
Water Needs of Rose of Sharon
This plant has relatively average water needs and can survive a bit of dryness. However, avoid exposing it to extreme water conditions like sogginess and droughts. These conditions may stress your hibiscus out and cause yellowing leaves or dropping buds.
Constantly check its soil and ensure it is moist to the touch but not overwatered to prevent root rot. Also, avoid watering its foliage to stop fungal spores from appearing and damaging your plant.
Fertilizer
This plant does well with a bit of assistance from a well-balanced slow-release fertilizer during the spring and summer months. Keep its feedings to every three weeks, then avoid fertilizing when seasons grow colder. Overfeeding may cause its buds to drop.
Pruning
Owners of this plant seldom prune it throughout the year as it does not grow wildly. Pruning is mainly done for shaping and removing dead branches. While technically a shrub, Rose of Sharon branches are frequently pruned to assume the shape of a tree.
Do your pruning in around late winter until early spring before its buds develop for its growing season. Pruning tips will encourage branching and, therefore, more flowers. Cutting to keep only two or three blossoms per branch can help it produce more prominent flowers.
Rose of Sharon varieties that re-seed abundantly also need pruning. Modern cultivations, however, have developed hybrid varieties that produce fewer or no seeds.
Growing Rose of Sharon From Cuttings
As previously mentioned, many Rose of Sharon hybrids are sterile and seedless. If you want to propagate more of your seedless varieties, you can take cuttings and root them. Doing so will also result in a plant identical to its mother plant.
This process is simple. Here is a quick guide to get you started on rooting Rose of Sharon from cuttings:
Step 1: Take your cuttings.
It is best to take your Rose of Sharon cuttings early in the same summer you plan to root them.
Not all of these are guaranteed to survive. Take more than you think you’ll need to ensure a higher success rate for propagation.
Step 2: Cut it to the correct length.
Take about 5 to 10 inches from newer, healthy stems. Each stem must still be soft and not hard and woody. Cut it at a 45-degree angle and prune it, leaving only a few of its topmost leaves.
Step 3: Place it into the correct potting mix.
While potting soils may be perfect for seeds, it isn’t ideal for cuttings. Your cuttings may be susceptible to infection if planted in potting soil during the propagation stage. Instead, use a soilless mix, as these are sterile.
You may also grow cuttings in water. Read further for more information.
Before placing your cuttings into your mix, dip the ends of your cutting in rooting hormone.
Insert no more than ⅓ of the cutting into your mix. Place it on a drip tray and water it immediately. Keep any excess water in the tray for the potting mix to absorb over time. Then, cover it with a clear plastic bag to simulate a greenhouse effect.
Step 4: Keep rose of Sharon cuttings away from the sun.
Place your pot in a shaded area. After a week, remove the plastic bag and begin gradually introducing your cutting to sunlight.
If done right, roots should appear within one to two months, along with a few new leaves.
Extra: Growing Rose of Sharon Cuttings in Water
You can also root your Rose of Sharon cuttings in water. The process is similar to planting them in potting mix with only a few variations.
To start, place your Rose of Sharon cutting in a container with about 2 inches of water. Next, cover it with a clear plastic bag. Then, it’s best to leave it in a place that receives a good amount of indirect sunlight.
While waiting for it to produce roots, spray it with water every day. Also, change the water every two to three days.
If growing more than one cutting, make sure to place them in separate containers. This way, rotting stems have no chance of contaminating healthy ones.
Wait until the roots grow to about 1 to 2 inches before planting in compost or potting mix. From there, gradually introduce your plants to direct sunlight.
Germinating Rose of Sharon Seeds
Rose of Sharon seeds germinate readily and do not require pre-treatment before sowing. Many traditional Rose of Sharon varieties abundantly drop seeds that, when left unattended, sprout on their own. Thus, you are bound to see success using any seeds you have bought or gathered from previous harvests.
Unfortunately, growing this plant from seeds will not guarantee a physical similarity to its parent plant.
Step 1: Harvest your seeds and prepare for planting.
Wait until mid-winter, when the seeds have dropped out of their pods and have ripened. Check if your Rose of Sharon seeds are viable by wrapping them in damp tissue paper or a paper towel. Let them rest for a week. If they absorb water and swell, they are suitable for planting.
When planting indoors, plant them around three months or 12 weeks before the official last day of winter.
Step 2: Prepare your pots or seed-starting tray.
Fill your pots or seed-starting tray with a soilless potting mix or sterile, humus-rich soil. If using pots, fill it up with about a half-inch difference between the soil and the rim of the top. If going for a seed-starting tray, fill each cell fully without packing the soil tightly to leave some breathing room.
Many gardeners recommend adding a little milled sphagnum moss to the surface of your potting mix. The moss helps fight fungi growth that may damage your seedlings.
Step 3: Plant your seeds and place them in the right environment.
Plant your seeds about a quarter to half an inch deep in the center of each pot or cell. Ensure that each seed is covered fully but loosely with potting mix.
Place them in a warm environment that gets direct sunlight, like a south-facing window. Keep temperatures at 75 to 80 degrees Fahrenheit to ensure successful germination of your seedlings.
Step 4: Water the rose of Sharon seeds regularly.
Water your seeds as soon as you plant them. Also, be sure to take note of the time you planted your seeds and mist them daily at the same time. Mist each pot or cell until the soil is entirely moist up to 2 inches deep.
Follow these steps correctly and see your Rose of Sharon sprout within two to four weeks.
Frequently Asked Questions About Rose of Sharon
Yellowing leaves may be from either a pest infestation or watering issues. If no pests are spotted, check your soil. It may be a matter of soggy, poorly draining soil. Lack of proper drainage causes water buildup, which suffocates your Rose of Sharon’s roots, leading to yellow leaves. Replant them in a well-draining potting mix.
Many factors cause dropping buds, but most of them concern your plant’s environment. While the Rose of Sharon can handle hot weather, constant exposure to temperatures over 90 degrees Fahrenheit can be harmful. In addition to prolonged heat, dropping buds are also caused by excessively low humidity.
If these conditions are not the problem, continue troubleshooting by checking your water and fertilizer. Dropping buds may be an indicator of overfeeding, so lessen your use of fertilizer. Also, check its watering conditions. Too much or too little water can also be the culprit.
You can encourage your Rose of Sharon plant to grow bigger flowers through pruning. Pruning early in spring or during fall and winter, right before your plant develops buds, can produce more abundant flowers. If done later in spring, removing some flowers and keeping only two or three can make the remaining flowers bigger.
Most Rose of Sharon varieties grow to great heights. However, Rose of Sharon also has dwarf varieties that are small enough for indoor gardening. The Lil Kim is a classic dwarf variety that only grows to a maximum of 4 feet. The Pollypetite, a newly developed hybrid, also only stands 3 to 4 feet in full maturity.
Root cuttings from the plant you want to duplicate to propagate a specific type of Rose of Sharon variety. Using cuttings will ensure its flowers are identical to the ones you want. Growing a plant from seeds may produce flowers that have characteristics different from its parent plant.