Hibiscus flowers rarely last more than one day, but flower buds generally are produced in large quantities over a long period of time.
Tropical hibiscus are not winter hardy in Minnesota and must be brought indoors if you intend to overwinter them. Plants can be outside in full sun during the summer. Hibiscus prefer 50-60% humidity and should be misted frequently. Plants kept outdoors will probably need daily watering. For plants kept indoors, the soil should be kept slightly moist. Fertilize with a potassium rich fertilizer every two weeks from April to September and once every month through fall and winter.
Hibiscus should be inspected periodically for aphids, spider mites, and scale. Spray Orthene if it is necessary. Yellow leaves are usually caused by abrupt changes in soil moisture and/or air temperature. It is normal for older leaves to yellow and drop in early spring and at the end of summer.
Hibiscus require a minimum indoor temperature of 60 degrees in order to avoid leaf loss. Prune back and repot in March in preparation for bringing them outdoors again.
Click Tropical Hibiscus Fact Sheet for a printable version of this page.
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