Hibiscus are perhaps one of the most iconic flowering plants on the planet, with their eye-catching blooms conjuring up images of tropical islands and exotic paradises. But these flamboyant flowers can flourish in homes and gardens the world over, even in the chilliest of climates. They may require a little more attention than some plants, but they more than make up for it with truly show-stopping blooms, sometimes lasting all year round!
Here’s our simple guide to growing these tricky yet terrific beauties, both indoors and outdoors.
What is Hibiscus?
Hibiscus is a large genus containing over two hundred species of flowering trees, shrubs, and herbaceous plants belonging to the Mallow family Malvaceae. Hibiscus are native to warm, temperate, tropical, and subtropical regions of Oceana, Asia, Africa and the Americas and are a key feature of local ecosystems, providing a valuable food source for everything from pollinating insects to reptiles like iguanas, mammals like deer, and even humans.
Cultivated worldwide as a popular ornamental, they are a versatile plant which adapts well to a huge range of growing conditions, including urban areas, wetlands, jungles, gardens, pots, beds, hanging baskets, and even indoors, depending on the species.
Hibiscus plants are instantly recognisable for their distinctive showy blooms, often associated with the tropical islands from which they originate. Each flower can reach diameters of around ten to thirty centimetres and consists of five broad, papery, ruffled petals. The petals open widely around a protruding central stamen that is often gold in colour. Hibiscuses produce flowers in a huge spectrum of rainbow colours, and the petals often feature contrasting or deeper coloured markings towards the centre.
Despite each individual flower lasting for just a day or two, perennial varieties can remain in bloom all year round if conditions and care are right. Deciduous varieties, on the other hand, bloom from summer through to autumn when they become dormant, shed their foliage, and sometimes die right back during the winter months before producing new buds and blooms the following spring.
Small varieties may only reach maximum heights of around thirty centimetres, whilst tree varieties can grow up to thirty meters tall. Regardless of size and species, hibiscus plants produce an abundance of glossy green foliage that is heavily adorned by their exuberant, showy flowers.
The history of Hibiscus
Despite being an ancient plant, and being widespread across many continents all along the expanse of the equator, hibiscus was not officially recorded by Western botanists until the late sixteenth century, although indigenous local knowledge and use of the plant dates back millennia. Captain James Cook brought the first hibiscus plant from Tahiti to Great Britain in the seventeenth century, where they were considered an unusual specimen at first. In the Victorian era, hibiscus gained great popularity as houseplants as a way to display both opulence and wealth.
It is thought by some that the name ‘Hibiscus’ is derived from the Ibis bird, who the Ancient Egyptians deemed to be sacred, although it is most commonly accepted that the plant takes its name from the Ancient Greek hibiskos, meaning ‘mallow’, and from the Latin hibiscum, meaning ‘marshmallow plant’, a plant which hibiscus is closely related to.
What does hibiscus symbolise?
Hibiscus plants hold several important meanings to the island and tropical communities where they are native.
On several of the Polynesian islands, a single red hibiscus flower worn behind the ear of a single woman indicates her availability for marriage. Its abundance and beauty mean it has also been adopted as the national flower of many island nations.
In Hinduism, red hibiscus flowers are thought to symbolise the tongue of Kali, the Goddess of Power, and worshippers often bring offerings of hibiscus to her and Ganesha, the God of Beginnings.
In Ancient Egypt, the red hibiscus flower symbolised lust and romance. Teas brewed from red hibiscus petals were thought to be an aphrodisiac.
Uses and benefits of hibiscus
Aside from its inherent beauty, the hibiscus is also an incredibly functional plant and has been used by humans for many purposes for millennia.
The brewing of hibiscus into a delicious tea is a common practice the world over, and it is thought to deliver numerous benefits to those who drink it. The deep scarlet-coloured drink tastes similar to cranberry juice and is known to have diuretic effects, lower blood pressure and cholesterol, and aid in weight loss. Hibiscus tea is also packed with antioxidants to help purify the body and repair cell damage.
Local communities and cultures where hibiscus grows wild have known of the benefits of this fantastic flower for centuries. Records show parts of the hibiscus flower have been used in traditional herbal medicine to alleviate ailments such as liver problems, wound healing, respiratory illnesses, and circulatory disorders.
All parts of the hibiscus plant are edible for humans, and in fact, you can safely pick and eat a flower straight from the plant, although more commonly, hibiscus is used as an ingredient for jams, sauces, spices, relishes, and of course, teas. In fact, hibiscus plants have formed part of the staple diets for communities where they are native for millennia.
The vivid coloured hibiscus petals are a common ingredient in traditional and natural dyes. Because they are non-toxic, they are commonly used for organic food colourings and hair dyes, as well as in fabric dyes. The flowers are even used as shoe polish in some cultures since they release a black liquid when crushed!
Aside from the health benefits gained from drinking its tea, many cosmetics take advantage of the benefits of hibiscus too! When used as a treatment for hair, hibiscus can help to stimulate growth, repair heat damage, and moisturise dry hair. For the skin, hibiscus can boost the natural production of collagen, helping to plump skin and reduce wrinkles, as well as being an excellent exfoliator and moisturiser.
Whilst traditional medicine has long utilised the medicinal properties of hibiscus, modern medicine too is beginning to embrace the myriad therapeutic benefits of hibiscus. Early scientific studies show that hibiscus extracts may aid with weight loss, lowering blood pressure, stimulating metabolism and even inhibiting the growth of cancer cells.
Types of hibiscus
There are more than two hundred individual species of hibiscus in the genus, and most of these can be categorised into one of two groups; either tropical or hardy.
Tropical hibiscus varieties, as the name suggests, originate from warm, tropical regions and cannot withstand cold temperatures below 1°C. They will bloom all year round if temperatures are consistently warm, and their foliage is evergreen, although they can become dormant in cooler temperatures. The most common tropical hibiscus variety is the rosa-sinensis, or Chinese hibiscus. Tropical hibiscus plants are generally smaller than hardy varieties.
Hardy hibiscus originates from cooler areas and are cold tolerant, perennial shrubs and trees. They are often cultivated in northern climates due to their ability to withstand much colder temperatures than their tropical cousins. Their toughness doesn’t mean they are any less beautiful, however, and they produce plenty of show-stopping blooms all throughout summer and often well into autumn. The most common hardy hibiscus variety is the syriacus, which is commonly known as the Rose of Sharon.
Caring for your Hibiscus
The level of care that your hibiscus requires will depend on whether it is a tropical or a hardy variety. Tropical varieties are fussier, and generally need to be grown indoors, whilst hardy varieties are less demanding and can be grown outdoors even in cold climates.
Hardy hibiscus care (Outdoors)
Positioning and Planting
Hardy hibiscus will grow happily in ground borders or in containers, but take note of the variety before planting, since larger tree varieties won’t do well in pots. Try to position your hibiscus somewhere that is sheltered from harsh winds but will receive lots of sunlight and warmth during the summer. Leave about three feet of space around young hibiscus plants in borders, since they can spread vigorously as they mature.
Hardy hibiscus does best in moist, loamy soil. You can amend existing soil in borders by incorporating plenty of organic matter to deliver additional nutrients to these hungry plants. They will happily live in heavier, wetter soil that most other plants won’t tolerate.
Position your hardy hibiscus somewhere that receives at least six hours of sunlight each day. If you live in a very sunny area, position them somewhere with dappled afternoon shade, since the very intense sun can scorch their foliage and harm their flowers. A lack of sunlight may cause your hibiscus to become leggy and struggle to flower.
Temperature and Humidity
Hardy hibiscus likes to be positioned in a warm area of the garden. During heatwaves, when temperatures consistently exceed 30°C, your hardy hibiscus may begin to shed its beautiful blooms, so consider providing it with some extra shade or moving it indoors where temperatures are cooler. Hardy varieties like plenty of humidity, so positioning them near to a pond or water feature is a great way to ensure the ambient moisture is adequate.
Hardy hibiscus are a thirsty plant, so keep an eye on the soil, whether in a ground border or a container, and water whenever the very top layer of soil has dried out. During the summer you may need to water your hardy hibiscus every day to sufficiently quench its thirst and make sure you water deeply rather than lightly. Larger, more established plants will need more water than younger ones.
Fertilise your hardy hibiscus during spring and summer with a high potassium food to encourage plenty of fabulous flowers. They are a particularly hungry species, so weekly feeds will yield the best results.
Once established, prune your hardy hibiscus annually in early spring to maintain your desired shape and size. In the autumn when it starts to drop its leaves, you can prune the stems right back to the ground for the winter. Don’t worry, the underground root system will sustain your plant and fresh new buds will emerge in the spring. Deadhead your hibiscus throughout summer to promote abundant blooms.
If you have been successfully growing a tropical hibiscus outdoors, but you live in a cooler northern climate where temperatures are likely to regularly drop to below 10°C, you should overwinter your plant indoors. Temperatures below 1°C will kill a tropical hibiscus, so unless you bring it indoors, you should treat it as an annual. Treat it as you would a houseplant over the coldest months, and when the last frost passes in spring, you can move it back outside.
Hardy hibiscus are much more tolerant of the cold and are able to survive temperatures below freezing, so you won’t need to lift them for winter. Instead, mulch generously around the base of the plant to protect it from frost damage. Don’t panic if it begins to drop leaves or appears to die back completely. It will return with fresh new buds in late springtime.
Tropical Hibiscus (Indoors)
Potting and Repotting
Tropical hibiscus adapts well to being grown in pots, just like most other houseplants. Select a shallow pot, since this helps to direct energy away from root growth and towards flower production. Container-grown hibiscus will begin to wilt when they become very root bound, although they tend to bloom more abundantly when they are just a tiny bit pot bound. Aim to repot your hibiscus every two to three years. The best time to repot is in early spring, just before your hibiscus starts actively growing.
Just like hardy hibiscus, tropical varieties like a rich, fertile substrate. Enrich a standard houseplant potting compost with lots of nutritious organic matter such as sphagnum moss. Try to add some acidic materials since they do best in slightly acidic soil.
Tropical hibiscus like plenty of sunlight, so position yours somewhere close to a south-facing window where it will receive at least six hours of bright, indirect light per day. During the hottest summer days, move your hibiscus to a slightly more shaded position whilst the sun is at its most intense, or use a translucent voile to diffuse the sun’s most intense rays. Too much direct sunlight can scorch the foliage, but too light sunlight can cause your hibiscus to become leggy or struggle to bloom.
Temperature and Humidity
Tropical hibiscus are perfectly suited to the average household temperature, as they do best when temperatures are consistently above 15°C. You can move your tropical hibiscus outdoors during summer if you wish, but make sure nighttime temperatures won’t drop below 10°C. If the temperature in your home remains consistently warm all year round, you can expect your tropical hibiscus to bloom all year round too!
Tropical hibiscus like moderate-to-high humidity levels that replicate their tropical origins, so placing yours in a kitchen or bathroom is ideal. During winter when central heating dries the air out, consider misting your plant or placing it on a pebble tray to increase the ambient moisture.
The trick to watering your tropical hibiscus is to do it regularly and generously, especially during spring and summer when tropical hibiscuses are actively growing. As soon as the surface of the soil dries out, you should water it again. Allow the pot to drain thoroughly after each watering to avoid oversaturating the soil. Periods of drought will cause the foliage to droop and the flowers to drop. You can reduce your watering schedule quite a bit during winter if your tropical hibiscus becomes dormant.
Tropical hibiscus needs plenty of high potassium fertiliser to produce abundant blooms. Weekly feeds are needed throughout spring and summer, but you can stop feeding during autumn and winter if your plant becomes dormant.
Indoor hibiscus should be deadheaded regularly throughout the blooming season to promote new flowers. You should also prune the stems to keep their size manageable, their shape attractive, and prevent them from becoming leggy.
Propagating your Hibiscus
Whether you are growing a hardy hibiscus outdoors, or a tropical hibiscus indoors, the method of propagation is the same. The easiest way to do it is by taking cuttings.
Select a young, healthy stem with plenty of new foliage, and snip off a section about four to six inches long. Remove most of the leaves, but keep those at the very tip of the stem intact. Fill a pot with rich, fertile substrate and place the snipped end of your cutting into the soil. If you want to speed up the rooting process, you can dip the end of the cutting in some rooting hormone before planting. Place the pot somewhere moderately warm with plenty of bright, indirect light and keep the soil evenly moist, but not soggy. After a couple of months, your cutting will start to produce healthy new roots and leaves. Once these roots become established, you can transplant your new baby hibiscus to its intended growing position.
Is hibiscus toxic?
Although not toxic to humans, some varieties are toxic to pets if ingested, so keep them well out of reach of inquisitive paws.
How long will my hibiscus live?
A well cared for hibiscus can enjoy an exceptionally long life, with some traditional varieties living for fifty years or even longer. Newer cultivars and hybrid varieties, on the other hand, have a somewhat shorter lifespan of around ten years.
What does hibiscus smell like?
Most hibiscus varieties give off little to no scent at all, but what they lack in fragrance they more than make up for with their flamboyant flowers.
Hibiscus brings an enchanting exoticism wherever it is grown, whether that be indoors or in the garden. And whilst they may not be the easiest of plants to care for, they certainly are one of the most stunning and will reward your efforts with their iconic tropical blooms for many years to come.