ABC's of Hardy Hibiscus (Hibiscus x moscheutos) Hibiscus is not only tropical but there are many varieties that can live in zone #5. Be patient, they are slow to appear in the spring.
Perennials Hardy, Site author's observations
full, at least 6 hours
once established can tolerate normal conditions, need to be kept well watered until established, the more water the greater the number of flowers and the larger the plant
Soil & Site
average, not soggy
large crepe textured round flowers, 3-4 inches up to 10 plus inches depending on variety, many different colors form red, white, pink, cranberry, plum, mauve, raspberry, etc., last only one day, turn into a mushy mass on day 2
green to burgundy red
in zone #5 the stems die back to the ground
3-8 feet high, up to 6 foot spread depending on variety
after the first killing frost cut back to about 6-10 inches, flowers wilt to a mushy mash the second day, if this bothers you they can be removed, sometimess staking of branches will help prevent them from breaking
cuttings, hybrids will not come true from seed
The size and number of flowers of this plant depends to a great extent on the growing conditions. The ones I have grown, usually fend for themselves. Will give additional water when needed. I drive past a planting of hardy Hibiscus where the gardener has supported the plants with a low decorative fence and waters on a regular basis. These plants are twice the size of mine with double the amount of flowers. A stunning display for their garden.
Plants are hardier than many people think. In one of the coldest winters (2014) not one of my plants died and only lost a few at the garden center. In zone #5 they are very slow to emerge, I seem to get 3-5 years of life from these plants.