Shrub althea 'Admiral Dewey'

Hibiscus syriacus 'Admiral Dewey' | Also known as: Rose of Sharon 'Admiral Dewey', Rose mallow 'Admiral Dewey' | Rating: 0 votes | Print / Pdf

Native to Asia, Hibiscus syriacus is also known as rose of Sharon and rose mallow. It can grow to 13 feet in height. It has pink trumpet shaped flowers with large protruding yellow anthers. The flowers only last a day, but they keep blooming all over the summer. It seeds easily and so is sometimes considered invasive. This species is the national flower of Korea where it has always grown. It was introduced to Europe in the 16th century. It will grow in most soil types, with a preference for moist soil with good drainage. Grow this one in full sun or partial shade.

Rate it:
Plant
Known dangers?
  • no
Height [m]
  • 2
Spread [m]
  • 1.5
Dominant flower colour
  • White
Flower Fragrance
  • No, neutral please
Flowering seasons
  • Early summer
  • Mid summer
  • Late summer
  • Early autumn
  • Mid autumn
Foliage in spring
  • Green
Foliage in summer
  • Green
Foliage in Autumn
  • Green
Propagation methods
  • semi-ripe cuttings
  • Greenwood cuttings
  • layering
Growth habit
  • Bushy
  • Erect
Environment
Acidity
  • Neutral
  • Alkaline
Hardiness zone
  • Z5-9
Heat zone
  • H9-1
Winter temperatures [°C]
  • -29 - -1
Heat days
  • 0 - 150
Moisture
  • well-drained
  • well-drained but frequently watered
Soil type
  • sandy
  • Clay
  • chalky
  • loams
Sun requirements
  • Full sun
Exposure
  • Sheltered
Usage
Standard category
  • Trees & shrubs
  • Shrubs
Grown for
  • Attractive Flowers
Creative category
  • Kid Approved
  • For Beginners
  • Colours
  • Show-offs
  • Bonsai
  • Neighbour repellant
  • Roses & classics
Garden type
  • Cottage garden
  • Coastal
  • Containers
  • City
Garden spaces
  • Flower beds
  • Hedges and screens
  • Borders
Gardening expertise
  • beginner
Time to reach full size
  • up to 20 years
18 Related plants
Hibiscus

Hibiscus

PLANTS Hibiscus

There are hundreds of species in the hibiscus genus. They're known for their bright showy funnel shaped flowers and are native to warmer, tropical climates. Hibiscus come in many sizes, from small plants to shrubs and trees. They have oval leaves that usually have a toothed edge. The flowers come in all sorts of colours, including red, yellow, pink white and orange and purple and are between 4cm and 18cm in diameter. With some species, the colour of the flowers changes with age. Hibiscus flowers are often used to make a tea and they can also be candied to create an attractive garnish for dishes.

Hibiscus Cranberry Crush

Hibiscus 'Cranberry Crush'

PLANTS Hibiscus 'Cranberry Crush' | -34°C - -1°C beginner Full sun

Hibiscus 'Cranberry Crush' is also known as Swamp mallow 'Cranberry Crush’. This new variety is something rather special. It's low growing with toothed leaves rather like a maple, and large deep red flowers that grow from several points on each stem, rather than just from the top of each stem like most varieties, meaning that you get an abundance of flowers. The blooms grow up to 8 inches across making them a very impressive sight, the petals have a slightly ruffled look to them and they overlap each other. Hummingbirds are particularly attracted to these flowers.

Hibiscus Old Yella

Hibiscus 'Old Yella'

PLANTS Hibiscus 'Old Yella' | -34°C - -1°C beginner Full sun

Hibiscus 'Old Yella' is also known as Swamp mallow 'Old Yella'. If you love plants that put on a big show, you'll love Old Yella. The main feature of this plant is the size of the flowers. Each flower head can easily reach 12 inches in diameter, that's pretty spectacular! The flowers are a pale yellow colour with a red centre, the petals are ruffled and the shape of the flower head is similar to a hollyhock. It's pretty easy to grow but will produce the best floral display if you plant it in moist soil and keep it well watered as well as ensuring it has plenty of air flow around it. Dead head it regularly to keep it looking at its' best, and prune it right back after it has finished flowering.

Hibiscus Summer Storm

Hibiscus 'Summer Storm'

PLANTS Hibiscus 'Summer Storm' | -34°C - -1°C beginner Full sun

Hibiscus 'Summer Storm' is commonly known as Rose Mallow ‘Summer Storm’. This award winning hybrid is gorgeous. It has large deep red wine coloured leaves that resemble a maple leaf. The flowers too are totally stunning, they are a lovely pale pink colour with deeper pink veins running through them, and a red centre. The size of the flower heads also adds to the massive impact of this variety, being around 8-10 inches across. This variety also benefits from a longer flowering period than most other hibiscuses. It's a fast grower and will reach a height of around 4-5 feet tall. It will tolerate poor soil and should be kept well watered.

Hawaiian white hibiscus

PLANTS Hibiscus arnottianus | beginner Full sun

Who doesn’t want to experience Hawaii every day? Well now you can with hibiscus arnottianus or Hawaiian white hibiscus. This large shrub or small tree has oval-shaped leaves, which are sometimes hairy on the undersides. The exotic flowers produced by this plant provide a tropical paradise welcome to garden visitors. White to pale pink with red staminal columns, these flowers are an ideal way to create a gorgeous holiday retreat in your own garden. Hawaiian white hibiscus grows in most kinds of moist soil with good drainage and should be planted in an area that receives full sunlight. This is a sensational screening or hedging plant and also a beautiful choice for trellises. Alternatively liven up a patio or courtyard garden by growing Hawaiian white hibiscus in a container or turn your flower beds and borders into a dazzling display that will have you opting for a getaway at home in your own amazing backyard.

Hibiscus moscheutos Luna Blush

Swamp mallow

PLANTS Hibiscus moscheutos | -29°C - 4°C beginner Full sun

Hibiscus moscheutos is a hardy perennial plant that’s often called rose mallow or swamp rose-mallow. It produces large tropical looking flowers in the summer months. H. moscheutos is best planted in full sun with compost that retains a lot of moisture. Naturally found in bogs, rose mallow can tolerate large amounts of ground moisture, and fades quickly in drought conditions. It’s ideal for use in rain gardens or sunny positions next to ponds where moisture content is high. When used in containers, h. moscheutos must be watered well.

Chinese hibiscus

PLANTS Hibiscus rosa sinensis | -29°C - 4°C beginner Full sun

Bold, vibrant and utterly captivating, hibiscus rosa sinensis or Chinese hibiscus knows how to pack a punch with large, show-stopping flowers that feature frilly petals in a range of lively shades, including bi-coloured and multi-coloured varieties. The leaves are lustrous and tooth-edged, forming an attractive background for showcasing the flowers. Ideally suited to loamy soil with good drainage, Chinese hibiscus should be grown in full sunlight to partial shade and watered freely except during winter when it requires little watering. This plant brings great pizzazz to a tropical garden and looks sensational in borders. This shrub is a great option for concealing walls and for growing on trellises, but it can also be planted in a container and placed on a patio or within a courtyard garden to give a riot of exotic colour and beauty.

Hibiscus syriacus

Shrub althea

PLANTS Hibiscus syriacus | -29°C - -1°C beginner Full sun

Native to Asia, Hibiscus syriacus is also known as rose of Sharon and rose mallow. It can grow to 13 feet in height. It has pink trumpet shaped flowers with large protruding yellow anthers. The flowers only last a day, but they keep blooming all over the summer. It seeds easily and so is sometimes considered invasive. This species is the national flower of Korea where it has always grown. It was introduced to Europe in the 16th century. It will grow in most soil types, with a preference for moist soil with good drainage. Grow this one in full sun or partial shade.