Showy Hardy Hibiscus

The Beauty of Dinner Plate Hibiscus

By Ava Green

The big, bold, showy, dinner-plate-sized flowers on hardy Hibiscus (Hibiscus moscheutos, also known as Swamp Rose-Mallow) are unforgettable, to say the least.  What a surprise it is to discover that this perennial plant not only survives our Zone 6, Southern Ontario climate, but thrives here! And despite its dramatic, exotic look, this plant is genuinely easy to grow. 

What Hardy Hibiscus Loves

Hardy hibiscus thrives in full sun with moist, well-drained soil and produces huge, gorgeous flowers without spreading and becoming invasive. As a rule of thumb: more sun means more blooms.

Give it ample space as it can grow 4-7 feet tall depending on the variety. Plant it 2-3 feet apart in a border, rain garden, meadow, or beside a fence, stream or pond, and it will thrive there for many years. Because it prefers consistently moist soil, avoid planting it near a brick wall or a driveway as these areas tend to dry out quickly.

When transplanting, add compost into the hole, and keep the base of the stem level with the surrounding soil. Don't mound soil or mulch up around the stems. If you’re planting your hibiscus in the fall, aim to do it at least 6 weeks before the ground freezes so the roots have time to settle in. 

If you'd like a bushier, more compact shrub, you can cut these plants back by half in June.

One thing to keep in mind: hardy hibiscus is very slow to start in spring. Don’t be alarmed if it doesn’t show new growth until the soil warms to around 21º Celsius.

What We Love About Hardy Hibiscus

If everything mentioned above isn’t enough to entice you, there’s more! 

Their enormous, ruffled flowers can reach a full foot in diameter, growing on sturdy, woody stems that stay upright on their own; no staking required. While they resemble their tropical hibiscus relatives, or Rose of Sharon (Hibiscus syriacus), hardy hibiscus produces noticeably larger blooms. They flower mid to late summer in dreamy shades of white, pink, and red.

Beyond their beauty, Hibiscus moscheutos is also a valuable native plant of Ontario. It attracts hummingbirds, dragonflies, and butterflies, and in areas prone to stormwater runoff, it helps absorb moisture and reduce erosion.

Seeing Is Believing

Stop by Eising Garden Centre and see the stunning beauty of hardy hibiscus in person. You just might fall in love too!