I have a nice growth of Tiny Gem ( I think that's what they are called) currant tomatoes, says they are the smallest EVER, with tiny fruits, but also tiny leaves, and sized for a hanging basket. They were seed planted, in bottomless translucent plastic cups, and are out in garden, right now.
can they be grown inside, on a window shelf, south facing window- 4 hours of strong sunlight a day, through winter months?
Just found your posting...by now you've probably discovered that tomatoes need at least 8 hours of direct sunlight to perform well - which means outside in warm weather or inside a heated greenhouse in the winter with supplemental light and nutrients.
I've seen advertisements for those lighted "plant stations" which is an expensive way to grow a compact container type tomato indoors.
I am currently growing currant tomatoes in the GH. The plant is loaded with blooms and has quite a few tiny tomatoes on it. I am providing no extra lighting but I do realize the days will continue to grow shorter till the winter solstice ~ December 22nd. Then, they will grow longer again ~ yea!
If you try to grow them ( and I will encourage you to experiment ) be sure to shake the tomato plants to encourage self pollination. Also continue to gently fertilize. I think you will find they won't require as much water when growing in these conditions.
They may not be as bountiful as if they were grown in the summer outdoors but then it isn't summer outdoors. A tomato at this time of year will be savored. Kristi