Dear Carina, Where possible, place plants especially on both sides of the balcony. If the plants flower this would be `great.' For cactus, you can still place them in the balcony. Although it has been frequently mentioned that it is not auspicious to do so. Do so, if you really liked them else, where possible (in my opinion) try not to `use' them if you can. For a balcony, so long as it is within the house, it can be considered in the living area especially if you have sliding doors and immediately get to see it. Frankly, placing cactus is quite a subjective issue. For some people who are not aware of Feng Shui, in my opinion, so far, I do not see any ill effects on them..Back to the drawing board? Warmest Regards, Cecil