The hibiscus family is a large one, with over 200 individual species. Most of these are from warmer climates and it is fair to say tropical and subtropical regions.
It is a diverse family of plants and you can see this in your own garden. The small tree, Hibiscus syriacus, is a semi-hardy shrub that will sometimes produce blossoms in a zone 4 garden in a late fall. On the other hand, Hibiscus trionum, is an annual that will self–sow in the same USDA zone four garden and has delightful small yellow flowers.
This is a listing of some of the more common perennials you may find
This is the most commonly found “perennial” in the garden center today. It has been reliably hardy for me in a USDA zone 4 garden.
Sun: full sun to part shade
Bloom Color: various but mostly from whites through reds (and between) – new varieties coming from the breeders like crazy now
Bloom Time: late summer to fall
Height: 5 feet
Width: 3 feet
Propagation: Division or seed. Hybrids don’t come true from seed.
Hardiness: USDA 4
Lifespan: 5 years plus
Best Soil: average although this plant requires reqular watering (it is not a drought garden plant) and does well in a damp area
Potential disease problems: powdery mildew
Potential insect problems: Japanese beetles, sawflies.
Use: A tall border plant, or damp area plant next to ponds.
Growing Care Tips:
This is a very late plant to emerge in the spring and you’ll wonder if it’s dead or not. I’ve seen it emerge in July and then grow at considerable rates to flower by September.
It does require great air circulation or you may see some powdery mildew and other fungal problems. Do not crowd it in the perennial garden.
This is a good plant to grow in clumps of three for impressive garden performance and a hedge is also possible.
This is a southern plant also known as the Swamp Hibiscus. Native to Florida and Georgia and hardy to USDA 7.
I’ve lusted after these red flowers in mid-summer but unfortunately, they won’t live for me.
This isn’t as bushy as H. moscheutos being taller and skinnier (5-7 feet tall and 2-3 feet wide) with a more open leaf habit.
This is a damp area plant – a perfect bog plant and it will not thrive in the open garden without a great deal of water. It is also not attacked as drastically by Japanese beetles.
Another tender Hibiscus, hardy to USDA 7 (I tried it several times and failed miserably in USDA 4)
Pink blooms in late summer through fall and very late to emerge in the spring.
If you can find the seed and start it in January, you may treat this plant as an annual in the north.
It is another plant that requires consistent moisture and is less susceptible to Japanese beetles.
You may see it in more Southerly garden centers but it isn’t common at all in the north.
A final note:
Tropical hibiscus flowers are sometimes used in herbal medicine as a diuretic, to relieve pressure in the gallbladder, and to relax the uterus if you need your uterus relaxed. 🙂 A laxative, a component of diet foods (hydroxycitric acid -HCA, or hydroxycut) and you may indeed be able to buy the powder at health food or diet food stores. No recommendation is implied or given here – you have to consult your physician. I’m just passing it all along. This is one of those plants that modern medicine uses and conventional folklore (at least in Europe and North America) has pretty much ignored.