Hello, If I have posted this in the wrong section please forgive me, I am new to this forum. Here is a little background information. My mother gave me a hibiscus tree when I moved out, (I believe it is a tropical variety, as my flowers are very large and a sunset orange/red colour)I have had great sucess with it until recently. My plant is about 6 feet tall, and tree like. The upper "branches" are mostly woody with the last 6 inches or so green growth, leaves and buds. Since it has been with me it has kind of taken off like a shot. It gets lots of sun in the winter and in the summer I put it out on my balcony (both positions are south facing). Last summer it started to grow all crazy but I was too afraid to trim it. Now that it is indoors it has become a bit of a handful. But I digress. I have discovered white fly on my hibiscus. I believe it "caught" it from a passionfruit plant I had bought. (which is now completly dead due to white fly I am sad to say) I have used sticky tapes, and have sprayed with dish soap and water, but the problem is not subsiding. In frustration I just recently put out a pointsettia into the cold just to get rid of them. They are now spreading to my more hardy plants. Clearly it is not possible for me to put my plant in the shower to rinse off the bugs, but I was hoping that I could prune my plant down a bit which would help me control the situation. Herein lies my real problem! I have gone to several sites and watched videos, but I still am not sure what to do. Currently each "branch" (off of the "trunk") has little or no nodes. Its just stick (approx 3 feet) with leaves and a bud tip. Also, my plant has been flowering like it is living in the middle of the summer sun and I am lothe to cut the flower buds away. I have been feeding it (I just recently found out that I shouldn't be in the winter) and am wondering what on earth am I going to do with this behemoth. I would like to trim it down and create a more bushy "tree top" but am not sure where to start. The videos say to trim it in the early spring... well it's March 9th and some people would call that early spring and some would not. Also, some have said NOT to cut the woody parts of the plant as this would not encourage new growth (of green stems and buds) but the woody "branches" have grown a bit out of control. PLEASE SOMEONE HELP! Any hints, tips and advice would be greatly appreciated! Thank you!!
For the pruning, if you have to prune back heavily, perhaps do it in stages to allow the plant time to adjust to the loss of green leaves. Regarding fertilizer, you can basically define spring as the time of year in your particular house where you don't need the heat on so much, and so the house keeps a higher humidity, close to outdoors, and so the plant can grow hogwild without weak, twiggy growth that is susceptible to bug infestations like you have now. To treat the whiteflies, you can first vaccum up as many as you can get. Then the most important step, every time the plant needs to be watered, for awhile, drag it outdoors and use the "flat" setting on your hose sprayer to blast the bugs over and under the leaves and in all the little crotches. This also cleans the leaves of sap, dust, spidermites, etc.; and allows the plant to better battle the bugs itself. keep going with the sticky traps and hang them right from the branches. That should be more than enough for healthy plant that hasn't been fertilized in the late fall or winter. The next level up is insecticidal soap, like Safer, right after you water & sharp-spray the plant. If you don't mind getting into plain poisons, the next step would be neem oil spray or capsaicin sprays. These are both produced from plants, but are refined poisons (supposedly harmless to humans if used correctly). The final, full nuclear option are the chemical sytemic insecticides. There are a couple rated as safe for indoor houseplants, but I really hate to go that far. If you concentrate on getting the plant very healthy without fertilizer (silicon additives, used like a fertilizer, can help a plant resist chewing insects), then the sharp spray of water will do almost everything you need to do. :)
In my experience with Hibiscus rosa-sinensis, you can prune it radically. But then, I keep mine outdoors year-round in Florida, am a laissez-faire gardener, and rather like using power tools. My hibs were cut down dramatically due to unusually cold weather in early winter. One of mine has stems that are thicker than your wrist, and they've still sprouted plenty of new growth. Admittedly, I rarely prune them down that far, and hibs that old will have a lot of bushy growth with stems of many diameters, so it wouldn't have been a great loss if the thickest oldest trunks did not sprout new growth. If it helps, all green growth from last year was toast and all leaves dropped off, but I'm getting flowers now two months later. I know you are loathe to cut off flower buds, but you don't have much of a choice if you want to get rid of your whiteflies. It's not specifically the flower buds, but all the growth with all the crevices that you need to reduce. I'd follow Tom's advice as closely as you can, with my encouragement to not be timid with pruning. (Except I really don't use power tools on my herbaceous plants. Hand pruned each of hundreds of stems.)
Thanks so much to everyone who posted! I have started to trim my hibiscus, I am going to wait in between cuttings to give it a chance to recoup. Sadly it is now starting to drop leaves much faster. I hope I can control the the flies before they ruin my plant!! Once again thanks for your prompt replies and all your help!!
