Hardy Hibiscus, Rose Mallow, Swamp Mallow 'Morrison's Mammoth Rainier Red'

Hibiscus moscheutos

Family: Malvaceae (mal-VAY-see-ee) (Info)
Genus: Hibiscus (hi-BIS-kus) (Info)
Species: moscheutos (mos-KEW-tos) (Info)
Cultivar: Morrison's Mammoth Rainier Red
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4-6 ft. (1.2-1.8 m)


24-36 in. (60-90 cm)


USDA Zone 5a: to -28.8 C (-20 F)

USDA Zone 5b: to -26.1 C (-15 F)

USDA Zone 6a: to -23.3 C (-10 F)

USDA Zone 6b: to -20.5 C (-5 F)

USDA Zone 7a: to -17.7 C (0 F)

USDA Zone 7b: to -14.9 C (5 F)

USDA Zone 8a: to -12.2 C (10 F)

USDA Zone 8b: to -9.4 C (15 F)

USDA Zone 9a: to -6.6 C (20 F)

USDA Zone 9b: to -3.8 C (25 F)

USDA Zone 10a: to -1.1 C (30 F)

USDA Zone 10b: to 1.7 C (35 F)

Sun Exposure:

Full Sun

Bloom Color:


Bloom Time:

Mid Summer

Late Summer/Early Fall



Other details:

Unknown - Tell us

Soil pH requirements:

6.1 to 6.5 (mildly acidic)

Patent Information:

Unknown - Tell us

Propagation Methods:

By dividing the rootball

From herbaceous stem cuttings

From seed; sow indoors before last frost

From seed; direct sow after last frost

Seed Collecting:

Allow pods to dry on plant; break open to collect seeds

Foliage Color:

Unknown - Tell us

Bloom Characteristics:

Unknown - Tell us

Water Requirements:

Average Water Needs; Water regularly; do not overwater

Where to Grow:

Unknown - Tell us


This plant has been said to grow in the following regions:


Bigelow, Arkansas

Palisade, Colorado

Boise, Idaho

Belle Chasse, Louisiana

Bellaire, Michigan

Swartz Creek, Michigan

Westland, Michigan

New York City, New York

Oxford, North Carolina

Kingston, Pennsylvania

Myrtle Beach, South Carolina

Broaddus, Texas

Philippi, West Virginia

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Gardeners' Notes:


On May 30, 2010, popsal from Palisade, CO wrote:

i have a red hibiscus that is 3 plants woven together, and the top is ball-shaped. I want to know if this is hardy enough to plant outside Zone 5, and how do I keep the shape through the winter? Up until now, I have been bringing the plant indoors and it blooms until March, then stops until I put it out in the spring. Any suggestions?


On Mar 3, 2008, Chikkin from Boise, ID wrote:

I am having trouble finding a photo of the actual seed themselves. Can someone post one? I planted what I think are the seeds (very tiny) but ....??


On Sep 24, 2004, justlearningduf from Plattsburgh, NY wrote:

I grew this and several others in my garden this year. I bought them for $1.00 at the end on the year last year. I put them in a new garden with composted manure. I'm a definite zone 4 and we had -30 to -40 but with a good snow cover.
They were slow to start but, are at least 5 foot and have been blooming since last month and show no signs of stopping


On Apr 13, 2004, Witchie from Belle Chasse, LA wrote:

This plant tolerates the deep south well.I have found that it is slow to produce any growth until early April.I have cut it down after a heavy frost to leave about 4 inches of woody growth.The seed pods should be collected after the pods have turned brown.Usually, the plant will produce pods the second growing year.This plant tolerates my zone's Tropical Season well; hence would recommend it for windy, rainy areas.(Plant should be well staked; however)