I can only be sorta general here....perhaps someone else knows better... The cold (or drought stress) is to induce flowering, not really fruit set. Fruit set needs certain minimum temperatures, amongst other things. Sorta makes sense then why citrus often flower in the early spring (after winter lower temps and subsequent rises in springtime temperature) and then set fruit in that warmer temperature. A lot of citrus are not really tropical but subtropical. Some types (prolly more tropical ones like Keys or kaffir) instead get stressed by relative drought patterns (water stress). For some reason citrus flowers when under some sort of stress (I don't know enough to say if this is something that other plants tend to do since I frankly *don't care* lol...). I have come to recognize sudden, out-of-character, excessive flowering in a tree as a sign of severe stress of some sort (heck come take a look at my backyard I can show you plenty of examples, and for me that is usually the signal to *please remember to water*--oops--lol). I think of it as an evolutionary concept--if the tree is heading towards that great compost bin in the sky, then it should hurry and try to leave something behind for the genetic pool. I'd venture to guess that those trees that tend to be everbearing ones maybe get stress signals from smaller variations in temperatures (like typical diurnal changes) or perhaps from extreme sensitivity to changes in water availability. Which may explain why I hear of how some cultivars are everbearing in some climates but not others. I think the range needed to induce flowering is not very low. Like in the 50-60's range or something like that. I think I read it here on this forum from a long time ago? And so for the orignal poster of this thread, in theory you can try to induce some stress by changing irrigation patterns but I've never deliberately attempted to do so. The other option is to wait it out and see what the tree does. Maybe it needs more time between the chilling and spring temps to develop those flowers, since the colder weather was atypically late. Shuttin up now. HTH.

tsmith2579, There is no draft our pellet stove blower is blowing in a different direction. The plastic pot has the drip pan attached on the bottom so if there is a little excess water that's where it goes and it probably does sit there until it evaporates. I do have it in the sunniest part of the house with 2 plant lights on them. Are the halogen shop lamp better than the plant lights? Are plastic pots ok to plant orange trees in? Right now I have them planted in potting soil and a little peat moss,and I am in the process of transplanting them into more drainable soil because I don't know what else to try because of leaves and baby fruit falling off. Any other suggestions?

Columnar apples are excellent choices for containers. And while not really trees, so are blueberries. But neither are very 'exotic' :-) Dwarf citrus also do well in containers but need some sort of winter protection. Perhaps placing your container on a dolly or attaching heavy duty casters to something like the half whiskey barrel would facilitate movement. Any of the dwarf or minidwarf fruit trees should do well in large containers. Check to see if your choices need a second type for pollination. There's a number of different exotic fruiting plants typically available at local nurseries and seem to be more available each year but most of these tend to be shrubs or vines rather than trees.....maybe you might want to consider enlarging your choices. The other consideration with growing fruit in small spaces is to espalier the various trees. It takes some time for training and attention to pruning but you can get a lot of different trees in to very small spaces this way. You could actually construct an espaliered fence around your backyard.

Wallaman, you have a ton of suckers growing up from the base of the tree trunk. You should remove those ASAP and return this tree to a single trunk beauty. It is a navel as fireball stated above and looks to be at least 25-30 years old. You have some twig die back in the center of the tree that needs to be cut out before spring, no big deal branches die sometimes we just need to help the tree get rid of them. It will sprout new branches and the void will get filled back in with time. Your tree is very nice, wish I had a big full tree like that. It probably hasn't been fertilized in a long time, if ever at all. In about 6 weeks from now, sprinkle about 5 lbs of good citrus fertilizer under the canopy and water it in for about an hour with an old school lawn sprinkler that moves back and forth (unless you have irrigation). Then repeat in May and August and sit back and enjoy the show the tree puts on. Your tree will be so full of blooms by the end of February beginning of March it will be incredible and the smell will be equally astonishing. Hope this helps, Best of luck and keep us posted on its progress. Evan