For you folks who live in 85% of the country, who get frost at one time or another, you have to protect your plants in the winter.  This is one of the most important elements in the care of your tropical Hibiscus.  The better you care for your Hibsicus during Winter, the faster they will start blooming in Spring

There are several different zones within the U.S. So the way to care for your plants during Winter will vary depending on where you live.  Many of the zones can be categorized into one of the following: snowy places (or very cold) and wet and chilly places. See Climates for more information.

Before bringing in your plants for the winter, make sure you give them time in the shade outside.  This transition is called hardening off your plants.  This makes the trip inside the house less stressful and eases them into their new environment. 

Plants that change their environment too quickly will lose leaves and weaken the plant.  The same is true when taking your plants back outside again.  Take them from the house and put them in complete shade for a week or so before trying to give them direct sun. 

There are a few things you should look for during the Winter months to keep the plants as healthy as possible.  If your plant is outside and exposed to temperatures below freezing, look at the leaves.  If your leaves are turning black and mushy, then the plant has been exposed to freezing or below and is in danger of dying.  The remedy is to get your plant to a warmer area. 

If it looks like your plant is wilting even though it has water, check the roots.  They should be nice and white and smell clean.  If they are brown and smell like decaying matter you have a root fungus.  The easiest way to correct this is to dip the roots into a 10% bleach solution, give it new soil and place it back in the pot.  Try to keep the soil medium a little on the dry side. 

If you keep your plants outside all year, the most important thing you can do is to keep your plants out of the rain.  They can handle the occasional frost as long as they are dry.  They love water as long as they are warm.  But the combination of wet and cold is disasterous.  The idea is to mimic the tropics. 

So, if you have chilly or cold winters and Winter is not your dry season, put them under an overhang, porch or covered patio where they stay dry.  In general, if your plants are exposed to cold weather (in the thirties or below) keep them on the dry side.  Only water them enough to keep them alive.  Do not allow them to wilt but you should not keep them soggy either.