Answer #1 ·
John Heider's Answer · Hi Nancy - My wife loves her hibiscus and protects them from cold winter conditions by moving them to the garage at night and during cold days. She does this when the temperature starts to get below 40 degrees F. Normaly our days are warmer than yours so her plants can still get the daily sun and then brought back in at night if needed. You may want to keep your plant in all winter and if so this may help you with overwintering in your home or possibly your garage.
Before you bring your plant inside, spray with an insecticidal soap or horticultural oil, then prune back your plant quite a bit, to within 4-5" of the main stems. This does a few things: it will help eliminate the bugs and insects that hide in the plant before they get inside your home. They like to hang out in the tips of the branches, in the newest growth. You also give the plant less to have to worry about. There will not be as much growth to feed.
If you want the best chance of having a healthy plant with flowers next summer, your plant needs to rest indoors during the shorter days from October till April. do not push it to keep blooming indoors and leave it full of old foliage as this will exhaust the plant, produce spindly growth and invite bugs. As with any houseplant, do not fertilize at all during the winter. Fertilization will force your plant to grow.
When inside, the leaves will probably turn yellow and fall off - this is normal. They will regrow when they are ready. In the meantime, water very sparingly! If you want to try to preserve the leaves that are on it, give it 3 or so hours of sun or direct light, fluorescent lamps can help. Do not keep the soil wet. To much water will also cause the leaves to drop. It is best to let the soil become almost bone dry before soaking it again. Do not let any water sit under the plant in trays, etc.
Your plant will rest and may not produce new leaves until late February or March. This is normal too. In early spring after any expected frost you can take your plant outside and fertilize. Hopefully this effort you have done during the winter will reward you with a beautiful plant to enjoy for another year on your deck.)