Many of the following sites refer to more than one aspect of hibiscus care.
Q and A, CARE, TIPS, TROUBLESHOOTING
http://www.trop-hibiscus.com/q.a.html
http://www.exotic-hibiscus.com/pages/hibiscus.htm
http://web.wt.net/~strhibs/tips.htm
POT CULTURE
http://hibiscus.freeservers.com/hibiscus/care.html
PRUNING
http://www.trop-hibiscus.com/bfertins.html
PESTS
http://www.geocities.com/SoHo/Atrium/2006/bug/bug.htm
http://www.trop-hibiscus.com/bfertins.html
Plant and Pest Diagnostic Laboratory at Purdue University
http://www.ppdl.purdue.edu/ppdl/expert/White_Flies.html
University of Kentucky
http://www.uky.edu/Agriculture/Entomology/entfacts/veg/ef303.htm
FERTILISING
http://www.trop-hibiscus.com/bfertins.html
http://web.wt.net/~strhibs/growtips.htm
WINTER PROTECTION
http://www.gardenguides.com/TipsandTechniques/winter.htm
WINTERISING - POTS
http://www.trop-hibiscus.com/gindr.html
http://www.trop-hibiscus.com/svenska.html
http://www.trop-hibiscus.com/trop-hibiscus/mn.html
http://www.exotic-hibiscus.com/pages/hibiscus.htm
http://oakridger.com/stories/031998/gar_hibiscus.html
WINTERISING - GROUND
http://web.wt.net/~strhibs/tips.htm
the following is from this site-
FREEZE AND WIND DAMAGE
Hibiscus are tropical plants and do not tolerate cold weather. Well watered and fertilized plants will fare better. Blankets, cardboard or a thick layer of mulch or straw will help. Do not spray to ice over the plants as they will kill them. Plastic, while better than nothing, is poor protection. Do not prune until Spring and prune into living tissue.
http://www.hort.purdue.edu/ext/winmulch.html
NO BLOOMS
http://web.wt.net/~strhibs/growtips.htm
See Pots