We all love the idea of a tropical wilderness—the foliage and sunshine-y flowers all in one place together. After all, when we go on holiday, we tend to take a lot of photos of local flora, don’t we? There’s something downright magical about being surrounded by so much color and fragrance. The good news is that you don’t have to wait until your next vacation to enjoy beautiful, tropical blooms. With the help of this essential guide on how to care for the heavenly hibiscus plant, you too can bring a touch of the exotic into your life.
There is always a bit of confusion over which variety of hibiscus plant to purchase, and rightly so. The much-loved hibiscus is part of the spectacular mallow family, or Malvaceae in its true Latin name. Within this family there are well over two hundred species. These range from annuals and perennials to shrubs and trees.
Since there is such a great amount of choice out there, it can be difficult to know which varieties are suitable for growing as house plants, which are suitable for planting out in the garden. I hope this guide will set a few minds at rest, and give you all the information needed to make the correct choice for either your home or garden.
All hibiscus varieties have bright, colourful, showy, trumpet-shaped blooms, and a prolonged flowering period—which is why we love them. These gems are perfect for both container and garden planting, and although some varieties are considered to be fully hardy against frost, they perform best in a sunny, warm and sheltered position.
Read on to learn how to grow and get the best from your hibiscus, by following the easy steps listed below.
Choosing Your Hibiscus Plant
There are many varieties to choose from, but the main distinction is that some are frost hardy and some are not. Frost-hardy hibiscus are suitable for planting out in the garden. These are in the form of woody shrubs with long stems. They have typically ovate, toothed, bright green leaves arranged alternatively on their stems, and large, pretty, trumpet-shaped flowers. These can grow to around three metres in height.
Frost-Hardy Hibiscus
Frost-hardy hibiscus are suitable for USDA hardiness zones 5 through 8, though hardiness depends on the individual species. By contrast, the non-hardy types will only thrive outdoors in growing zones 9-11. These will die if exposed to frost, so they need to be taken indoors in autumn.
For my personal hardy hibiscus favorites, let’s start with Hibiscus syriacus ‘Red Heart’. This is a deciduous beauty that produces large, white blooms with striking red centers (hence its name).
The Hibiscus syriacus ‘Blue Bird’ variety is another deciduous form similar to ‘Red Heart’, but with impressive, deep lilac-blue flowers.
A stunning pure white variety is ‘White Chiffon’, which has large, almost double white flowers which can grow up to 10 centimetres in width.
Its sister, ‘Blue Chiffon’, is just as stunning though, with semi-double pale blue flowers, laced with purple-red hearts.
Tropical Hibiscus
The tropical hibiscus species originate in China and other far Eastern countries. When found in their native tropic and sub-tropic environments, they can be seen in the form of full-grown trees. These hibiscus varieties are grown as tender house plants, and are likely to reach a height of about two metres when fully grown.
Their large, trumpet-shaped blooms vary in color from yellow to orange, fuchsia, to purple. Some varieties are multicolored, and others have a variegation on the leaves, giving the foliage a marbled effect.
Due to their native natural habitat, they require tropical growing conditions such as warmth, sunshine, and plenty of light. If you’re aiming for a hibiscus that can be grown indoors, then the evergreen Hibiscus rosa-sinensis ‘The President’ is a super choice. It bears large magenta pink flowers with pretty, pollen-producing central yellow anthers.
Another favourite in this category is the Hibiscus rosa-sinensis ‘Best Friend’. Its large, orange-red blooms have a yellow margin and white heart, which look totally tropical. The Hibiscus rosa-sinensis ‘High Heaven’ is my final favourite, consisting of double white flowers laced with a deep pink heart, and long yellow anthers.
Planting Medium
All Hibiscus plants like well-drained, humus-rich soil or compost. This can be achieved by adding aggregate or vermiculite to your soil (or compost), to aid drainage. You should also add a good feed of acidic fertilizer (such as a rose feed), leaf mould, or even coffee grounds. These will aid root growth whilst promoting flower and foliage production
Selecting the perfect Planting Spot
When choosing your planting spot, remember to research how large the plant will be when fully grown. This will enable you to gauge the correct amount of space needed for your hibiscus to flourish. For garden planting, the perfect spot will be sunny, warm, and slightly sheltered. It’s important to allow up to around 3 metres of space for the plant to grow into.
If you plan on container planting your hibiscus, ensure you have a large enough pot. It needs to be able to house your root ball comfortably, with a couple of centimetres of space all around for extra growth. These like quite a snug fit, but that said, they need a little growing room too. Place your potted hibiscus in a well-lit, warm site (ideally indirect sunlight), and well away from drafts.
Caring for your Plant
Your hibiscus will need to be kept well-watered throughout the flowering period, which begins in late spring and lasts right through to late summer. Creating all of those perfect flowers is thirsty work!
Feed your hibiscus every two weeks throughout the flowering period to get the most out of your plant. To do this, you’ll need to use a liquid fertilizer specifically formulated for house plants. Just make sure you only fertilize when the soil is already moist.
Alternatively, a slow-release granule feed can be added to your container, or on the soil at the base of your garden plant. Most slow-release feeds add essential nutrients promoting plant health and growth for up to six months and are activated when moist.
Tender hibiscus varieties can be placed outside during the warmer summer months, but must be overwintered indoors.
Watering should be reduced in the wintertime when no flowers are being produced. At this time of year, only water your hibiscus when the growing medium/soil feels dry to the touch.
Pruning and Maintenance
Hibiscus requires some gentle maintenance in order to truly thrive. Gentle pruning encourages new growth, and the plant should be examined regularly to see whether it has outgrown its current container, and needs to be repotted.
All old growth on garden plants can be cut back hard in the spring. Young Hibiscus plants can be tip-pruned in early spring to promote new growth and a bushier appearance. Shoots that are thin and non-productive can be removed.
Re-potting can be carried out in February-March when the plant is still dormant.
Pests, and Disease Problems
Like all other plants, hibiscus are vulnerable to a number of different issues. Below are a few of the more common disorders you may come across while tending your garden.
Leaf Problems:
Leaf yellowing is a sure sign that your hibiscus needs more light, while yellow and white blotches on the leaves is a sign of too much direct sunlight—it’s known as “leaf scorching”.
Curled and pinched leaves should be lifted and checked from underneath for aphids, white flies, spider mites, and mealybugs. A suitable pesticide can be used to eradicate these bugs, as per its instructions.
Black or brown spots on the leaves is a sign of a fungal infection. Remove all infected leaves, discard them, and treat the plant with a suitable fungicide, as per its instructions.
Bud Disorders
Premature bud drop is a sign of a physiological disorder and an unhappy hibiscus placement. In almost all cases, this issue is caused by lack of food or water, which is easily remedied. If, however, this should continue, think about moving your hibiscus to a more suitable site.
Companion Planting
Hibiscus is a favourite for many gardeners, myself included. It provides easy maintenance, great all-season color, and a lovely flowing form. Their appearance mixes well with other shrubs such as the Spirea nipponica ‘Snowmound’ cultivar.
This particular spirea is a deciduous shrub with prolific clusters of small white, cup-shaped flowers on long arching branches. Many grasses also complement hibiscus’ flowing form. A few complementar options include Pennisetum setaceum ‘Rubrum’ and Miscanthus sinensis ‘Kleine Silberspinne’.
Place Hibiscus syriacus ‘Blue Bird’ towards the back of a mixed shrub and flower bed. By doing so, you have the perfect background for planting your favourite cottage garden perennials. Think dreamy delphiniums, pink hollyhocks, golden rudbeckia, and candy-coloured dahlias, all making up the perfect informal cottage garden.
By following our simple guide above, everyone can find and grow the perfect Hibiscus plant and bring a touch of the tropics back home.