check out the top thread on this forum
there are alot of good links to good info -
I have about 15 non stop tuberous begonias that i store over the winter
some in peat moss - some in vermiculite
both methods seem to work for me
I've been in the process of bringing begonias and other plants in for winter, thankfully I'm over half way there. First I hose them down really well, then I suds them up with soapy water, sponging off larger leaves and the rims and bottoms of the pots, and allowing sudsy water to flow through the potting mix. Then I rinse them well and flush the pots with water till I see no more suds, and allow them to dry over night. I haven't seen anything nibbling on the begonias, but if I do, I add some Neem to the soapy water solution (which also helps prevent fungal infection). Mostly just trying to get rid of any spiders or insect egg cases so the house isn't full of crawly things this winter. All of these are non tuberous varieties that won't go dormant in winter (my attempts to save tuberous begonias last winter were a flop- all rotted :-(...but I'll try again, LOL) They need to come in before first frost, which we've had a light frost already. As far as bedding types, I just take cuttings now and keep those going through winter; they seem to perform better than bringing mature plants in, and it saves space. Red Dragon begonias are the ones I treat this way so I'll have plants for hanging baskets and containers next year- saves lots of $!
Cane types and some other fibrous rooted types do well for me as regular house plants with no special care. I give Rex begonias humidity trays and keep them in a room where I keep a ceiling fan on; the humidity and air circulation seems to keep them happy.
Thanks for your wonderrful advice. As a gardener, I instinctively did as you stated above. I sprayed mine with both neem and insecticidal soap and let them air dry over a few hours ( it was a warm day). Then I brought them indoors. I may have 10 left to do.
I know that Iron Cross and Fireflush like more humidity so I intend to place them in a fish tank to increase the humidity. I noticed there were some white specks on the fireflush already. I hope it's not mites already. I will treat it again as you've suggested above.
I also have a Begonia grandis which is currently in the ground. Do you think I should move the whole thing in or just a cutting?
B.grandis is winter hardy for me too, but it may get a bit colder where you are. If its in a protected spot and/or mulched I think it should be ok outside. They produce those little bulbils in the leaf axils that you can start new plants with; I wonder if those could be stored through winter to ensure you don't lose them? Or perhaps they could be stored potted, but dormant.
The white spots sound more like mildew to me too, but I'm already seeing some spider mites. Strangely, I'm seeing them on some Elephant Ears that are still outside. Typically I don't see them till they've been in the house for a while, and the humidity and temps have dropped. Nights have been getting cool here, and we're still in a drought, so I guess the conditions are right for them outside. Just not a battle I was expecting to start this soon!
I usually don't see spider mites on begonias but do on EE's. I usually hose off spider mites which helps keep their numbers low. Cut off the worst leaves and dispose of them as needed.
Mealy bugs can be a pest on begonias. I don't use anything strong on begonias either (nor any other houseplant for that matter). Neem has a funky odor but appears safe from all the literature and I do use it from time to time. Alcohol for spot problems such as mealy bugs. Soap sometimes but not that much.
Neem is all I use for spider mites, and like hcmcdole, I've not seen them on the begonias. As long as I stay on top of it and use it about every 2 weeks, I don't see any activity. It does stink, but not really any worse than other chemical sprays, and that goes away when it dries.
I have a large Angel wing I have brought inside for the past two winters, I give it a haircut, and start the cuttings for friends. Make a solution of 1/2 cup bleach and10 gallons water and dip the plant, pot and all,after I have trimmed it, this has taken care of the bugs. I keep it in my office with a south facing window for the winter. Spring comes and I repot it and put it back outside. It really likes the north side of the patio near the pond, shade and humidity. It and my streptocarpas, have been going for three years and every year they get bigger and better.