|How well do hibiscus grow in a place like Portland, OR and what do I need to know about them to help them succeed?|
|Let's hope you have the perennial hibiscus (Rose-Mallow), rather than the tropical (Chinese) hibiscus. The perennial hibiscus is a hardy deciduous shrub that dies back in the winter months but springs to life when the weather warms. Planted in a sunny spot it will produce new stems each spring, that will flower during the summer. Water moderately during the growing season and mulch the soil with organic matter to help conserve moisture and to suppress weeds. Chinese hibiscus is best kept as a houseplant that's taken outdoors during the spring and summer months. This plant thrives on bright light and humidity indoors and out. Try to find out which type of hibiscus you're growing so you know whether to plant it out in the garden, or in a container that you can move with the seasons.
There is also a group of perennials in the rose mallow group called Hibiscus. These large plants need full sun and a rich moist soil and produce large crepepapery blooms in mid to late summer -- also quite lovely. Some common varieties you might see are "Lord Baltimore", "Southern Belle" or the dwarf "Disco Belle". These are late to emerge in the spring so mark the spot where they are planted and be very patient.
Once you've figured out which plant you're growing, you can take precautions necessary.
Lots of people grow hibiscus as houseplants during the winter, putting them outdoors for the summer months. Ideally, plants should be allowed to gradually adjust to indoor conditions after growing outdoors all summer. They're more likely to retain their leaves, and less likely to attract pests. When the daytime temperatures reach a minimum of 60F this spring, gradually acclimate it back to the outdoors by exposing it to a little more sun each day over the course of a week. Reverse the process in fall when you bring it inside.
Hibiscus like average household temperatures and very
bright light. They also want moist, but not soggy soil. Mist the leaves regularly to add some moisture to the air. If the plant gets too leggy, you can pinch back some of the stems. Fertilize during the spring/summer months (March through August as a rule of thumb).