Hi - I'm trying to get back into gardening, but I live in the city and all I have is space for potted plants on windowsills. I've got a couple herbs going - basil, oregano, mint. That's been nice, but I really want to get some veggies. Any recommendations for veggies that could survive this king of upbringing? Something that mostly extends upwards rather than outwards, and/or doesn't need a ton of space for roots?