By mid-fall, most plants have stopped flowering. However, if you’d like an autumn bloomer, fall is the perfect time to plant hardy hibiscus, such as the beautiful Rose of Sharon. Discover varieties of hibiscus flowers and planting tips from The Old Farmer’s Almanac.
Rose of Sharon
Rose of Sharon (Hibiscus syriacus) is one of my favorite late summer shrubs. Hardy hibiscus is so tough the plant will come back year after year as far north as zone 5. In the same family (Malva) as hollyhocks, mallows, and okra, this hibiscus can have single, double, or semi-double blossoms in a wide range of colors including true blue—a rare color in the flower world. If you need a shot of blue to contrast with all the autumn yellows and golds, look for ‘Blue Bird’, ‘Azurri Blue Satin’, or ‘Blue Chiffon’.
Forming a multi-stemmed shrub that can grow to be 8 to 12 feet tall and 6 to 10 feet wide, they can be planted 10 to 12 feet apart to make a colorful hedge. If you prefer a standard tree-shape, the extra stems can be carefully pruned out to give it that appearance. Since they flower on new wood do any pruning early in the season to give the plant a chance to recover and regrow new branches. They require full sun to produce the most blossoms but will still bloom in light shade. They prefer moist, well-drained soil and love hot summers. Fertilize in the spring with some compost and mulch around the base to keep the soil moist.
To encourage bigger blossoms, you can pinch off the extra buds, leaving only 2 to 3 per branch but I’d go for quantity over size any day.
Luckily this is one plant that is not attractive to deer but the migrating butterflies and hummingbirds love it!
Note: Rose of Sharon is considered an invasive in some parts of the country. To avoid the excessive seedlings that cause this problem, look for a sterile cultivar that doesn’t produce any seeds.
Hibiscus moscheutos
If you want to grow some really huge blossoms look for Hibiscus moscheutos. Most of them have blooms that are easily 10 inches across. Talk about dinner-plate size! Though these giant satiny flowers look tropical, the plants are hardy to zone 4. Unlike Rose of Sharon, they die back to the ground each year but make an amazing amount of growth over the summer, eventually reaching 3 to 4 feet tall. They can be slow to emerge in the spring so be patient.
We grew a variety called ‘Southern Belle’ from seed but there are many other hardy hibiscus to choose from. If you want to attract hummingbirds try ‘Cranberry Crush’ or ‘Midnight Marvel’. Both have irresistible red flowers.
The flowers only last for a day or two but there are many buds coming along to prolong the show.
Some varieties have the added feature of red, maroon, or copper-colored leaves to add to the drama.
I just planted one called ‘Cherry Brandy’ that has green leaves with a red blush.
Planting Hearty Hibiscus
If you’re planting in the fall, here’s how to plant a container-grown plant bought at a nursery:
- Dig the hole in your garden twice size of root ball of plant.
- Mix the soil you dug out of the hole with mulch or compost.
- Take the plant carefully from container, keeping a hand on the bottom of the plant.
- Lower the plant gently into the hole, centering carefully.
- Backfill the hole with your soil/mulch mixture.
- In the fall, we don’t usually add fertilizer as we don’t want to encourage the plant to grow.
- Build a little well around the plant for the water.
- Tap the soil around the plant gently.
- Water in your plant with a nice drink.
- The plant will rest quietly all winter, awake in spring, and flower by mid-summer!
If you would like to add an exotic touch to your late summer garden look no further than the hardy hibiscus.
More Tropical Flowers
Love the look of tropical flowers? Another colorful tropical plant is canna. A tropical bulb canna is hardy in zones 7 to 11, cannas boast super-sized leaves and showy stalks of yellow, red, salmon, orange, pink, or bi-colored flowers that bloom in mid to late summer. Easy to grow, canna also attracts butterflies and hummingbirds! See the Almanac’s Canna Growing Guide.
Reader Comments
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Sharon struggles, hardy hibiscus takes center stage
My two rose of sharon trees struggle yearly to bloom. They were pruned into tree shape since I got them five years ago. I've kept the shape and tried pruning down to a couple buds in early spring to keep them small and perhaps get the buds to open by having less of them. But the tree grows four or more feet even after pruning. The flowers are doubles, which makes them very heavy when they don't open. Each year, a few more will open, but it's still mostly closed buds. This season, I skipped pruning and will see what happens. My hardy hibiscus, however, is ten years old and sits in the center of my front garden. Now at its full size, it's about 4 ft by 4 ft each summer by the time blooms form. Pretty much zero maintenance. Cut it to the ground after the first freeze, remove some of the faded blooms to keep it pretty during the bloom time, which usually lasts three to four weeks in late July through August. Yes, it takes time in the spring to get growing but by the end of May it's green enough to start looking good and fills in nicely with lovely foliage as a backdrop to annuals and other perennials. I highly recommend them for anyone with the space in full sun.
Rose of Sharon
I have I long line of rose of Sharon’s that are a mix of colors, They are absolutely beautiful!
However!! Every year they Japanese Beetles come along and destroy 75% of the blooms most before they ever get to open! I have tried everything I can find to read and so far it’s a battle I cannot win! Can you please give me some advice? They are around 18 years old and at least 15 ft. Tall
Thank you for any advice!
Rose of Sharon
Are you sure that rose of sharon is not attractive to deer? That doesn't seem to be my experience, even when there is an abundance of other forage in the immediate vicinity. Are certain varieties more and less susceptible? - thank you
Rose of Sharon
Your article is very misleading, the Rose of Sharon Altheae is a member of the same family as the tropical Hibiscus. The Mallow is also in the family as are Okra and cotton. However, you are talking about Rose of Sharon a cultivar and showing pictures of Mallows.
Photos of hibiscus
We reviewed your comment. All of the photos of hibiscus were taken in Robin’s garden. Hibiscus, althea, & mallow are all in the same family. Mallows have smaller flowers than the ones pictured (which are hibiscus which Robin grew from seed). Robin’s descriptions and Latin names are correct.We don’t find anything terribly misleading. Even if the Rose of Sharon is a cultivar, it is still a hibiscus, still in the same family, that does not change. We hope you enjoyed Robin’s contribution, nonetheless.
hibiscus worms
My hardy hibiscus plants have been eaten almost completely by small green caterpillars that leave huge holes in the leaves. This started two years ago and they destroyed my plants this year despite spraying a lot with BT. I cut them down to the ground and they regrew and are blooming in August. The caterpillars are back and eating the leaves again though. Any suggestions?
Sounds like the larvae of the
Sounds like the larvae of the Japanese Rose-of-Sharon moth, a non-native, brown moth. They can produce several generations of caterpillars each season. Here’s a link to some pictures. https://www.butterfliesandmoths.org/species/Anomis-privata?page=2
I would think that BT or an insecticidal soap would help cut down the population. Are there are too many to handpick and squash? I don’t like to resort to poisons since they adversely affect more than the targeted insect. Luckily Rose-of-Sharon is a tough customer and will come back. Unfortunately it sounds like these caterpillars will return as well.
SPLITING hibiscus plants
Can I split a hibiscus plant and have two plants from one?
Yes! You can dig up the whole
Yes! You can dig up the whole rootball in the spring or in the fall after it has stopped flowering and split it into two or more pieces if the plant is a large one. Replant those sections and they should be ready to blossom for you next season. You can also propagate them from cuttings.
porcupines
last summer we had an over abundance of porcupines living around the nearby woods.
(Apparently, a female took a liking to a tree in my yard and all the males were "visiting" every evening.)
Along with chewing our shed, they seemed to like our Rose of Sharon bushes - they ate everything on them over 2 feet above the ground and left the empty branches on the ground. Fortunately, both bushes rebounded this year and bloomed better than I have ever seen! Both bushes are now close to 3.5 feet tall and the amount of blooms were absolutely amazing.
Porcupines can do a huge
Porcupines can do a huge amount of damage in a garden! I’m glad that your Rose of Sharon survived their attack on its branches and recovered fully.
Angel Trumpets
How can I make my angel trumpet bloom . I’ve had it 2 years but no blooms
We have a friend who grows
We have a friend who grows gorgeous brugmansias every year. He has given us a few plants. Only one of these has blossomed so far. It is the oldest plant. He says that the roots need to be 2-4 years old to blossom really well. Full sun and lots of water are key. He waters his daily (we did not). Fertilizing often can help as well. He recommends fertilizing weakly weekly.