Updated/Fact-Chacked on May 16, 2022 by John
Rose of Sharon( Hibiscus syriacus), also known as Althea bush, is a beautiful deciduous shrub that belongs in the Hibiscus species of flowers. While it’s classified as a shrub, it can be trained into a tree by pruning. Unlike many other flowering plants and shrubs, the Rose of Sharon is a late summer flowering shrub. As such, it helps to bring out the summer landscape in your garden or front yard. It’s also available in different including Blue Chiffon, White Chiffon, Sugar Tip, Red Heart, among others. Here is everything you should know on how to grow Rose of Sharon.
Growing Hibiscus syriacus is quite easy even for beginner gardeners. Before you embark on a mission to grow althea, it is important to learn about the different varieties of this plant.
Contents
Popular varieties of Rose of Sharon
1. Azurri Blue Satin
This variety of the althea can grow up to 6ft wide and about 12ft in height. Due to its massive size, it demands a larger growing space. It produces blue blooms and a few seeds.
2. Purple Pillar
Purple pillar is a gigantic species of althea. When grown well, it can spread up to 3 feet and rise to about 16ft. You can prune it to mimic a tree, and it is also a superb hedge plant. Purple pillar produces beautiful purple flowers.
3. Sugar tip
Sugar tip is a unique variety of althea. While other species produce seeds, sugar tip is seedless. This plant produces blue-green leaves and light pink flowers. At its peak, it can only attain a height of 6ft. Therefore, it is ideal to grow in a small garden.
4. Lil Kim
Since this species of althea only rises to about 4ft, it falls under the dwarf category of rose of Sharon. Some of its qualities include burgundy throats and beautiful flowers. It is also suitable for small gardens.
Other Rose Of Sharon Varieties include
- Blue Chiffon
- Red Heart
- Blue Satin
- Blueberry Smoothie
- Lavender Chiffon
- Lil Kim
- Lucy
- Minerva
- Purple Pillar
How to Grow Rose of Sharon
Growing Conditions of Rose of Sharon
Although Rose of Sharon is quite easy to grow, it will only do well if the conditions are conducive. The best thing about Rose of Sharon is that it can withstand poor soil conditions, heat, and drought.
Here are the best conditions to grow althea.
1. Generous space
Depending on the variety of althea that you would like to grow, you’ll need to consider the space you have. Most roses of Sharon species are demanding in terms of space. If you are planting several, they should be 5 to 10 feet apart and at least 5 feet from the house.
2. Full sun
While Rose of Sharon can grow under partial sunlight but it thrives in full sunshine. Plant it in a location where it can get at least 5 hours of direct sunshine.
3. Well-draining moist soil
Althea plant will only thrive in well-draining and moist soil. If you plant in soil that retains water, its roots will rot.
4. Soil PH
Althea prospers in soil with PH levels within 5.5 to 7.5. If you want to be sure before planting the rose of Sharon, test your soil PH.
When to plant the Rose of Sharon
Planting althea at the right time keeps pests and diseases at bay. If you want it to not only grow but also thrive, plant it during the spring or fall.
How long does Althea take to reach maturity?
Rose of Sharon grows at the rate of 24 inches (2 feet) per year. It is a slow grower that requires a lot of patience. To attain maturity, this plant needs about 4-6 years.
How to plant Althea
Step 1
Remove the rose of Sharon from the container that’s carrying it carefully. If you are afraid of damaging it, cut the container attentively. If the roots are compact, spray them with water. This will loosen them.
Step 2
Dig a hole at the corner of your garden then gently put the roots of the Rose of Sharon into the hole. The rootball of the plant should be level with the ground.
Step 3
Once the root ball is settled, fill in the remaining spaces with the soil that you removed from the hole. To ease out the air from these spaces, tap the ground. Do not add more soil as this can choke the plant.
Step 4
Water the soil-filled area and the root ball. The water should be as deep as the root ball’s height.
Step 5
Try and conserve water after watering the plant. Some dead plants and wood chippings will come in handy. Use them to cover the area around the plant. Don’t worry about them decomposing as they will serve as they will form nutrients that will enrich the soil. However, you shouldn’t use freshly cut wood chippings. They should be at least 6 months or older.
How to care for Rose of Sharon
During the early stage, althea will need a lot of care. But once the plant establishes itself, the maintenance will be less demanding.
Watering
You can sustain mature althea with minimal watering. But during its first year, it will need frequent watering. Once or twice a week should do. Make sure the soil gets 1 inch of water every week.
Fertilizer
Althea does not need a lot of nutrients to grow. Not unless you start noticing leaf drops, yellowish leaves, and stunted growth, the organic matter you mix with the soil when planting should be enough.
Pruning
Do not prune the rose of Sharon when It is in its flowering stage. After the flowering period passes, start pruning. If you notice some dead branches, break them carefully.
Pests and Diseases
Althea is susceptible to pests and diseases. Some of the pests that are likely to affect the rose of Sharon include aphid, canker, Japanese beetle, and blight.
Common diseases that attack althea include leaf rust, leaf spot, root-knot nematodes, and bud drop.
If these pests and diseases attack your plant, use pesticides as directed to eliminate and cure your althea. When using these pesticides, wear the required protective gear. Remember not to use insecticidal soap or fungicides when the sun is scorching. If you follow the right practices when growing althea, this will tremendously decrease the chances of disease and pest
Growing althea is easy when the conditions are right. Caring for it will keep the plant rewarding you with a fresh bloom each year. If you desire to make your summer landscape more alluring, this is one of the best plants to grow. You will feel a great sense of pride when this plant eventually matures.

Mary shares a passion for gardening with her husband John, though she is more focused on growing veg on their allotment at St. Margaret’s Allotments, Durham. Mary also works in the lawn care industry and manages the lawns for the Durham University campus.