The showy blooms of hibiscus take center stage from late spring and continue to flower right through autumn. Each blossom lasts about 24 hours, with new ones flowering the next day. They may look delicate, but they’re tough! With warm weather and regular attention, they will add a ray of sunshine to your garden.
Evergreen varieties of hibiscus will grow in tropical to warm-temperate climates, provided the area is free of frost. Deciduous forms, such as Hibiscus Syracuse, will also grow in cool-temperate and frosty climates. Hibiscuses can be planted at any time of year, but it’s best to plant deciduous forms during autumn, so they have time to establish their roots before winter sets in.
Hibiscuses grow best in well-drained, slightly acidic (pH 6-6.5) soil. The one exception is H. Syriacus, which is tolerant of alkaline soils. Before planting, ensure you improve the soil with well-rotted compost or manure. These plants also grow well in pots.
During the growing season, water regularly, and ensure drainage is good. Mulch the surrounding area with organic mulch, straw, hay, or sugarcane, ensuring it doesn’t touch the stem. This will help keep the roots cool and moist in summer.
These plants respond well to fertilizer. Choose one that encourages blooms, and is high in nitrogen and potassium, such as Yates Thrive Soluble Flower & Fruit Plant Food or Miracle-Gro MaxFeed Flowers & Blooms Soluble Plant Food. You can also add a fish emulsion or seaweed extract to this feeding mix. Apply before and throughout the growing season (August through to March) as this will help intensify bloom color and promote healthy growth.
- Plants can be purchased from nurseries or started from seed.
- Seeds can be sown indoors 12 weeks before the last spring frost. See local frost dates.
- Soak seeds in warm water for one hour before sowing.
- Seeds can also be sown outdoors after the last expected frost date.
- Plant the hibiscus where it is not exposed to strong winds to avoid breakage of the long stems.
- Space plants 2 to 3 feet apart.
- Mature plants can be divided in the spring.
- Mulch around the plant to retain moisture and to provide protection for the roots.
- Water plants deeply and thoroughly.
- To encourage re-bloom, remove old flowers before they form seed heads or prune plants back by one third after a flush of bloom is finished.
- In early spring, remove dead stems from established plants and apply a balanced fertilizer.
- Scarlet Swamp Hibiscus (H. coccineus): This plant, also known as Texas Star, has 5-petaled, brilliant-red flowers.
There are many wonderful hardy hibiscus hybrids available. Here are just a few:
- ‘Lord Baltimore’: Red flowers.
- ‘Sweet Caroline’: Pink flowers with dark centers.
- ‘Blue River II’: Beautiful white flowers.
- ‘Kopper King’: Huge pink blossoms with red centers. It’s named for its dramatic copper-colored foliage.
Wit & Wisdom
- The plant has been used to soothe headaches, aching limbs, coughs, and inflammations.
- Hibiscus tea is made from parts of a different type of hibiscus, Hibiscus sabdariffa—also known as Roselle or Florida Cranberry. It’s native to West Africa but is now grown across Central America, the Caribbean, and even Florida.
- In Victorian times, giving a hibiscus blossom to a person meant that the giver was acknowledging the receiver’s delicate beauty. Learn more about the language of flowers.