Hi newgen, As per another post which may be same problem as yours, your plant probably has Phytophera, a fungal disease of which their is no easy cure, if any. Some chemicals are available that, in certain situations, do arrest the disease and some plants recover. Natural remedies do sometimes work as well, but by sound of your description of your plant, it is too late. In your case it may be possible to drench in chemical or dose heavily with good quality, rich compost. In doing so the disease will be either killed off by chemical or the improvement in plant's health, via compost and introduction of beneficial organisms, will defeat the disease.

Only other way to more closely ID your problem is to send in photos of plant, plant leaf etc.

Regards, Brian.

Brian,

Thanks for the email.
I think you nailed it. I've taken 2 photos of the leaves, showing phytophera infection as well as "black dot" disease, as discussed on this website: http://www.diynetwork.com/diy/gr_diseases_weeds/article/0,2029,DIY_13843_2276927,00.html

http://i9.photobucket.com/albums/a67/delldude/P3137036.jpg
http://i9.photobucket.com/albums/a67/delldude/P3137035.jpg

I had about 20 hisbiscus plants, and only 4 look barely alive. I'm gonna uproot them all and plant something else. Too bad.

Thanks again,

The "black dot" disease discussed on that page, is, as far as I can tell, "black spot," a disease that attacks only roses.

If your plants have Phytophthora root rot, and you still have some of the failing plants left, check near the base of the stem. To do so, scrape off a bit of bark ranging from just above the soil to about two or 3 inches above.

A reddish discoloration -- cinnamon-brown some say -- indicates the root rot.

If that's the case, you need to put in only those plants which resist the root rot, caused by a fungus which survives in the soil for *many* years.

It was said "Some chemicals are available that, in certain situations, do arrest the disease and some plants recover. "

No such products are available retail in the US.