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Balcony tomatoes need at least six hours of direct sunlight a day. Choose a compact or cherry variety if space is limited, and use a pot of at least 30 cm in diameter with drainage holes.
Water consistently, keeping the soil moist but not soaked. Uneven watering is the most common cause of split fruit and blossom end rot in container plants.
Feed every two weeks with a balanced tomato fertilizer once flowering starts, and support the main stem with a cane or string as it grows. Harvest when the fruit is fully coloured but still firm.