If you’re not familiar with rose mallow, get ready to be amazed, especially if you garden in a northern climate. This often overlooked native perennial offers all the exotic floral beauty of tropical hibiscus (Hibiscus rosa-sinensis) but is tough enough to overwinter outdoors in areas as far north as Minnesota.
Like tropical hibiscus, rose mallow boasts huge, vibrantly colored flowers, some growing to the size of dinner plates. But once your hardy hibiscus bursts into bloom, it will continue flowering until the first frost and then return again in spring for a repeat performance. Despite its tolerance for cold weather, rose mallow also loves the heat and grows equally well in balmy southern climates.
Common rose mallow, swamp mallow, swamp hibiscus, dinner plate hibiscus; also shares the common name hardy hibiscus with Hibiscus syriacus.
Fast. New growth is slow to emerge from dormancy in spring, but plants shoot up rapidly once they take off, growing as much as an inch per day.
Mostly native to swampy areas, rose mallow prefers evenly moist, humus-rich soil. If necessary, mulch to help retain moisture.
Midsummer until the first frost. Although the flowers only last a day or two, rose mallow is a prolific rebloomer.
Broad, triangular, and deeply lobed. Usually medium green, but some cultivars have deep purple, coppery red, or blue-tinged foliage.
The African mallow shrub, also known as Anisodontea capensis or cape mallow, is a beautiful and versatile evergreen plant that can add a tropical flair to gardens and landscapes. With its abundant pink, hibiscus-like blooms and soft, hairy leaves, this South African native is gaining popularity with gardeners across warmer climates. But like any plant, proper sunlight exposure is key to helping the African mallow thrive. So how much sunlight does this exotic shrub need on a daily basis?
Optimal Sunlight for Cape Mallow
The best location for cape mallow is in full sun. While it will grow in partial shade, it does not bloom as prolifically when it receives less than 8 hours of bright sunlight daily. Morning sun is preferable. In hot climates, some afternoon shade is acceptable.
Ideally, aim to place African mallow shrubs where they will receive at least 6-8 hours of direct, unfiltered sunlight per day. This level of exposure allows the plant to achieve optimal growth and the highest potential for abundant flowering. Morning sunlight, in particular, is beneficial for encouraging bud formation and blooms.
Some afternoon shade may be welcomed in peak summer, especially in regions with extremely hot summers. But in general, the more direct sun you can provide, the better your cape mallows will perform. When given sufficient sunlight, these fast-growing shrubs can reach mature heights of 5-6 feet tall and spreads of 3-4 feet wide. Proper sunlight will also keep the plant sturdy and full.
Effects of Insufficient Sunlight
While adaptable to partial shade, the African mallow shrub relies heavily on adequate sunlight for optimal health. When this sun-loving plant does not receive sufficient sunlight, some potential effects include:
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Reduced flowering and smaller blooms The prolific flowers are one of the main attractions of the African mallow, so insufficient sunlight can greatly affect the plant’s ornamental value.
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Leggy weak growth. Without enough sunlight, cape mallow stems become elongated and spindly as the plant reaches for light. This affects the shrub’s structural strength and overall form.
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Susceptibility to pests and diseases, Weak plants are more prone to infestations and infections Strong sun exposure helps keep the shrub resilient,
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Poor branch and root establishment. New growth may be stunted without adequate sunlight. Propagation success can also suffer.
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Leaf scorching. While cape mallow prefers full sun, extreme afternoon sun may damage leaves if the plant is not sufficiently acclimated. Insufficient sunlight does not properly harden growth.
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Premature leaf drop. Leaves may yellow and drop prematurely if the shrub cannot photosynthesize efficiently due to shade.
Providing Proper Sunlight for Cape Mallow
When growing African mallow shrubs, consider the following tips to ensure your plants receive sufficient sunlight:
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Conduct a sunlight study before planting. Track sunlight patterns across your garden to identify the sunniest spots. Also note any large trees or buildings that could shade the area.
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Space plants generously. Allow ample room between African mallow shrubs and other landscape plants to prevent competition for sunlight.
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Prune overhead branches. Trim back tree limbs or nearby plants that may be encroaching on your mallows’ light space.
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Use south-facing walls. Position plants along southern exposures of homes, fences or garden structures to take advantage of sun bouncing off these vertical surfaces.
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Pick sun-loving companion plants. Choose companion plants like lantana and plumbago that also thrive in full sun and won’t shade out your mallows.
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Provide supplemental light. Consider adding grow lights if you simply cannot provide 8+ hours of direct outdoor sunlight for your shrubs.
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Avoid reflected heat. While the African mallow prefers sun, beware of reflected heat from pavements or walls that can burn leaves.
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Gradually acclimate plants. Slowly introduce newly planted mallows to prevent leaf scorch. Start them in partial shade.
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Monitor for signs of stress. Watch for spindly growth, yellowing leaves or lack of blooms as signals more sunlight may be needed.
Caring for African Mallow in Sunny Sites
When growing African mallows in full sun, be sure to adjust your care routine to support the plants in their sun-drenched environment. Here are some tips:
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Water regularly. Check soil daily and water whenever the top few inches become dry. Prevent wilting.
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Mulch beds. Apply 2-4 inches of organic mulch like bark chips or pine needles around plants to conserve moisture and reduce soil temperatures.
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Fertilize weekly. Apply a balanced liquid fertilizer weekly during the growing season to replenish nutrients used in active growth.
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Check for pests. Monitor frequently and treat promptly any spider mites, mealy bugs or aphids before they spread.
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Prune selectively. Remove crossed, damaged or excessive branches. Limit pruning to shape plants and improve air circulation.
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Renew mulch. Replenish fading mulch before it completely breaks down to maintain moisture retention and weed suppression.
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Spray leaves. During periods of extreme heat, spray plants daily with water to provide evaporative cooling. Avoid wetting flowers.
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Add shade structures. In peak summer, consider temporary shade with structures like shade cloth to prevent leaf burn.
The Takeaway
ShrubsDiscover the right shrubs for your garden.
Summerific® Berry Awesome rose mallow. Photo by Proven Winners.
If you’re not familiar with rose mallow, get ready to be amazed, especially if you garden in a northern climate. This often overlooked native perennial offers all the exotic floral beauty of tropical hibiscus (Hibiscus rosa-sinensis) but is tough enough to overwinter outdoors in areas as far north as Minnesota.
Like tropical hibiscus, rose mallow boasts huge, vibrantly colored flowers, some growing to the size of dinner plates. But once your hardy hibiscus bursts into bloom, it will continue flowering until the first frost and then return again in spring for a repeat performance. Despite its tolerance for cold weather, rose mallow also loves the heat and grows equally well in balmy southern climates.
On this page:
Common rose mallow, swamp mallow, swamp hibiscus, dinner plate hibiscus; also shares the common name hardy hibiscus with Hibiscus syriacus.
3 to 8 feet tall, 2 to 5 feet wide
Fast. New growth is slow to emerge from dormancy in spring, but plants shoot up rapidly once they take off, growing as much as an inch per day.
Mostly native to swampy areas, rose mallow prefers evenly moist, humus-rich soil. If necessary, mulch to help retain moisture.
Midsummer until the first frost. Although the flowers only last a day or two, rose mallow is a prolific rebloomer.
White, pink, red, or bi-colored, often with a contrasting eye.
Broad, triangular, and deeply lobed. Usually medium green, but some cultivars have deep purple, coppery red, or blue-tinged foliage.
What to look for when purchasing rose mallow plants:
When shopping for rose mallow, look for plants labeled as indeterminate, which indicates that the flowers are produced all the way up and down the stems and not just at the tip, like determinate varieties. Indeterminate bloomers, such as those in the Summerific® series from Proven Winners, will produce flowers for months on end, giving you a longer season of interest. Summerific® plants are not prone to setting seed, which can be a big plus if you don’t want your plants to self-sow in the garden.
Summerific® Perfect Storm hibiscus. Photo by: Proven Winners.
In spring or fall, as long as there is no danger of frost.
In full sun (at least 6 hours daily). In hot climates, it may be necessary to provide some afternoon shade to prevent scorching of the foliage. Also provide shelter from strong winds, which can damage the delicate, crepe-papery flowers. Because of rose mallow’s preference for wet soils, it thrives in low spots and wetter areas along streams or ponds. However, it will tolerate a wide range of soil types if kept well-watered.
Start seeds indoors in early spring and then transplant outdoors once the weather warms or purchase potted plants from a nursery. When planting, be sure to give plants plenty of elbow room to accommodate their eventual spread. If necessary, amend sandy or poor soil with compost or other organic matter before putting your plants in the ground.
Because of its colossal blooms, rose mallow makes a bold statement wherever you plant it, so be sure to use it judiciously so it won’t steal the show from the other plants in your garden. It’s best used as a backdrop for sun-loving groundcovers or plants with strappy foliage that will add nice textural contrast to the broad leaves. Get more ideas for good companion plants to grow with rose mallow.
Use in combination with spring bloomers such as creeping phlox or Jacobs Ladder. Since hardy hibiscus are late to emerge, plants like these can carry the workload for the first half of the year.
Water regularly and up to twice a day in hotter weather, especially if growing in a container. Wilting leaves are a sure sign that your plant needs a good soaking. To avoid leaf fungus and other foliar diseases, water during the early morning hours rather than late in the evening.
Once new growth appears in spring, sprinkle a slow-release organic plant food around the root zone and then supplement with a water-soluble plant food in early summer, when the buds begin form, to boost flower production.
When properly planted and cared for, you can get many flowers from one rose mallow plant (shown is Summerific® Cranberry Crush). Photo by: Proven Winners.
When you see new growth begin to emerge in spring, prune back the old woody stems to about 6 inches tall to make way for the new foliage. To stimulate branching and promote a bushier habit, you can prune the tips of the branches in early summer.
Deadheading of spent blooms isn’t necessary unless you want to prevent seedpods from forming.
In colder climates, apply a layer of mulch around your plants after they die back in the fall to provide an extra layer of insulation. While plants are dormant, water only enough to keep the soil moist.
Rose mallow growing in a pot can generally be left outdoors unless temperatures are expected to drop below 20 degrees F for a prolonged period of time. During a cold snap, take precautions by moving the pot to an unheated interior space, such as a garage or garden shed, until the temperatures warm up again.
Particularly vulnerable to Japanese beetles and sawflies. Leaf fungus can also be a problem but is easy to control by maintaining good air circulation around the plant and by removing diseased leaves.
Mallow Plant Nutrition, Foraging for Wild Edible Malva Leaves
FAQ
How much sun does mallow need?
Where is the best place to plant mallow?
How do you care for African mallow?
Do mallow plants come back every year?
How much water does African Mallow need?
African mallow needs 0.8 cups of water every 9 days when it doesn’t get direct sunlight and is potted in a 5.0″ pot. Use our water calculator to personalize watering recommendations to your environment or download Greg for more advanced recommendations for all of your plants. Does your plant get direct sunlight?
Do mallow plants need a lot of Sun?
Mallow plants are attractive additions to beds, borders, and cottage gardens. Planting mallow in full sun eliminates the need to stake the tall varieties. It grows best in moist, well-drained soil conditions.
How big does African Mallow grow?
The blossoms attract bees and butterflies. The slender branches are sparsely covered with small, hairy, evergreen leaves. Low maintenance, drought and heat tolerant, African Mallow is a gem in the Mediterranean garden styles or patio containers, adding charm and color. Typically grows up to 24-36 in. tall (60-90 cm) and 18-36 in. wide (45-90 cm).
How do you grow African Mallow?
Fertilize more often during the growing season and in warmer and brighter climates. African mallow grows vertically and new growth will emerge from the top of the plant. African mallow can be grown outdoors in USDA Hardiness Zones 8a-11b. Find your local hardiness zone here . The seeds of African mallow can be used to grow new plants!