Answer: If your yellow hibiscus are the tropical kind, they may not live through the winter if you leave them outdoors unless you live in an area that does not freeze. Tropical Hibiscus can't tolerate freezes. However, if you live in an area with just a few really cold nights (below 32F), it may be possible to keep your hibiscus in the ground year round if the plants are covered during the coldest nights. A 'frost cloth' is one good option that can provide up to 5 degrees of frost protection. We know people who have had good luck covering their plants with tarps and then running Christmas lights under them too, to provide even more frost protection. Any type of heat source under the protective cover will help. Unfortunately, nothing will work in temperatures below 20F other than a real, heated greenhouse or other substantial structure. Or, you may opt to pot up your hibiscus plants and take them indoors for the winter, then take them back outdoors next spring.
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