Scarlet rose mallow
Hibiscus coccineus · Malvaceae
Brilliant scarlet flowers with five separate, narrow petals, like a pinwheel, on tall, red-tinged stems with slender, hemp-like leaves.
- Size
- 6½ ft tall, 3 ft wide
- Zones
- 6 to 9
- Light
- Full sun
- Flowers
- Mid July to early September
- Pets
- No toxicity recorded
- Job in a bed
- Specimen
A bed built around scarlet rose mallow
The planner designed this bed around scarlet rose mallow when this page was made: a 12 × 6 ft (3.7 × 1.8 m) naturalistic planting in zone 6, full sun. It chose the other plants from the 251 that suit those conditions and its wet soil, and says below why scarlet rose mallow stands where it does.
The plants
- 1 Scarlet rose mallow × 1, red
- 2 Stemless gentian × 22, blue
- 3 Horned violet × 13, purple
- 4 White turtlehead × 3, white
- 5 Gray's sedge × 3, green
- 6 Bowles' golden sedge × 4, chartreuse leaves
- 7 Oriental lily 'Casa Blanca' × 4, white
- 8 Snowdrop × 7, white
Why this plant
- The only open bowls. The others are trumpets, spires, globes and others. Shape reads at a distance, where colours blur.
- The only red. The one hot colour: every other flower here is cool or neutral.
Why here
- Anchors a back corner. At 6½ ft it is the tallest plant here, and the tallest close the ends of the bed, where they stand in front of nothing.
- A step in the back row. Next to white turtlehead (3 ft): no two neighbours there are the same height, so the back steps up and down like a skyline.
- One plant, alone. A feature plant is seen as an object, and needs clear ground around it.
Why now
- In flower for 9 weeks. From mid July to early September.
- Part of the bed's peak. With white turtlehead, Gray's sedge and oriental lily 'Casa Blanca' in early August: 4 kinds at once. No week has more.
Planned as a naturalistic planting: low grasses and groundcovers, the matrix, make up 62% of the planted ground. Scarlet rose mallow and oriental lily 'Casa Blanca' anchor the back corners of the bed: the tallest plants on the plan stand there. The scheme leans cool (blue and purple) and uses red for warmth, with white and green to calm things between them. Worth a second look, according to the Design check: heights.
The planner's own design check: 8 Excellent, 8 Good, 1 Needs revision. Its weakest point is height and scale: Heights average about 4 in at the front, 14 in in the middle and 4 ft at the back. Along the back row the heights step up and down, between 2½ ft and 6½ ft, and no two neighbours are the same height.
Open this bed in the planner Change its size, the sun or the style, move plants about, or swap one for another.
Where scarlet rose mallow goes in a border
At 6½ ft it belongs at the back of a bed. In the planner's ten height classes it is very tall (5 to 6½ ft). It is airy enough to see through, so it can also come forward and veil what is behind it.
Its job: specimen. A feature plant with a shape of its own. It stands alone with room around it, and repeats only at a distance.
A native of southern swamps, lighter and more open than the dinner-plate hybrids, so it can stand in the middle of a planting. Hummingbirds visit it constantly.
- Pond margins and wet soil
- Hummingbirds
- A tall, airy accent
What to plant with scarlet rose mallow
Plants recorded as good partners for it, and what each pairing does:
- Cardinal flower: in flower together for seven weeks, from late July; low enough (3½ ft) to stand in front of it; happy in the same wet soil.
- Blue flag iris: flowers first, late May to late June, so the spot is never empty; low enough (2½ ft) to stand in front of it; happy in the same wet soil.
- Swamp milkweed: in flower together for five weeks, from mid July; low enough (4 ft) to stand in front of it.
Questions about scarlet rose mallow
Does scarlet rose mallow need sun or shade?
Scarlet rose mallow grows in full sun (6 or more hours of direct sun a day).
It wants moist to wet soil, rich in organic matter, and plenty of water. It copes with soil that stays wet.
What zones does scarlet rose mallow grow in?
USDA zones 6 to 9. It is hardy to zone 6, which means it survives winter nights down to about 0 °F (−18 °C).
Gardening in Canada? Use the USDA zone for your town: Canada's own zone map uses different numbers.
When does scarlet rose mallow flower in my zone?
In zone 5 it flowers mid July to early September. As a summer flower it moves about half a week for every zone: earlier where it is warmer.
| Zone 6 | Mid July to early September |
|---|---|
| Zone 7 | Early July to early September |
| Zone 8 | Early July to early September |
| Zone 9 | Late June to early September |
Worked out from Hopkins' bioclimatic law: spring arrives about four days later for each degree of latitude north, and one zone is roughly two degrees. A warm spring or a cold one moves any garden two weeks either way.
How far apart should scarlet rose mallow be planted?
2½ ft (75 cm) apart, from the middle of one plant to the middle of the next. That is a little closer than its full width of 3 ft (90 cm), so a group knits into one patch.
It grows 6½ ft (200 cm) tall. Give it the full distance from anything taller, or it will lean out towards the light.
How many scarlet rose mallow plants do I need?
At 2½ ft apart, set out in staggered rows:
- 2 to fill 10 square feet (about 1 m²)
- 5 for a single row 10 ft (3 m) long
- 6 to fill a 4 × 8 ft bed on its own
In a mixed border, plant it as one, with clear ground around it: a feature plant is seen as an object, and a group of them is a thicket.
In the bed above, the planner used one in one group.
Is scarlet rose mallow poisonous to dogs and cats?
No toxicity is recorded for dogs, cats, horses or people, according to NC State Extension.
"Not toxic" is not "edible": a pet that eats a lot of any plant can be sick.
Do deer eat scarlet rose mallow?
They may. NC State does not list it as resistant to deer or rabbits. Where they visit, protect it, or plant it among ones they avoid.
What flowers after scarlet rose mallow?
Scarlet rose mallow is over by early September. These start as it finishes and carry the same spot on, so it never goes flat:
- Pink muhly grass: from mid September to early November, 3 ft tall, to stand in front of it and cover its fading stems.
- Garden chrysanthemum: from mid September to late October, 24 in tall, to stand in front of it and cover its fading stems.
- Korean feather reed grass: from late August to mid October, 4 ft tall, to stand in front of it and cover its fading stems.
What does scarlet rose mallow look like in winter?
Scarlet rose mallow dies down to the ground and there is nothing to see until spring. The old stems can be cut in autumn, or left until spring as shelter for overwintering insects.
Is scarlet rose mallow good for bees and butterflies?
Scarlet rose mallow is visited by pollinators, specialist bees, butterflies and hummingbirds.
It is native to the United States.
More Hibiscus
- Hardy hibiscus Hibiscus moscheutos
- Hardy hibiscus 'Kopper King' Hibiscus 'Kopper King'
- Hardy hibiscus 'Lord Baltimore' Hibiscus 'Lord Baltimore'
- Rose of Sharon Hibiscus syriacus
- Rose of Sharon 'Blue Chiffon' Hibiscus syriacus 'Notwoodthree' (Blue Chiffon)
- Rose of Sharon 'Diana' Hibiscus syriacus 'Diana'
- Rose of Sharon 'Sugar Tip' Hibiscus syriacus 'America Irene Scott' (Sugar Tip)
In these guides
- Plants for wet soil and rain gardens
- Salt-tolerant plants for roadsides and coasts
- Pet-safe plants for a sunny border
- Native perennials for pollinators
- Plants for hummingbirds
- Plants for butterflies
- Plants for bees
- Tall perennials and grasses for the back of a border
Every fact on record
- Type
- Perennial
- Size
- 6½ ft (200 cm) tall, 3 ft (90 cm) wide
- Plant
- 2½ ft (75 cm) apart
- Height class
- Very tall (5 to 6½ ft)
- Place in the bed
- Back, or further forward: it is airy enough to see through
- Flowers
- Mid July to early September; open bowls; red
- Leaves
- Fine texture, herbaceous; green
- Shape
- Upright, clumping
- Hardy in
- USDA zones 6 to 9
- Light
- Full sun
- Soil
- Rich, moist to wet
- Water
- High
- Feeding
- Moderate, in spring
- Family
- Malvaceae
- Comes from
- Southeastern U.S.A., GA to FL
- Attracts
- Pollinators, specialist bees, butterflies, hummingbirds
- Stands up to
- Salt, wet soil
Checked against NC State Extension. Flowering times are for zone 5: later in colder zones, earlier in warmer ones. Toxicity and spread information is a general gardening guide, not veterinary or medical advice, and invasive status varies by region. If a person or pet eats a plant, contact poison control or a vet. Check your local invasive species list before planting anything with a spread warning.