Answer: Unfortunately I am not certain if your window box is indoors or outdoors, if it is indoors you might try some of the flowering jasmines such as "Maid of Orleans" which blooms over a long period, although not all the time. If it is outdoors your might try one of the smaller forms of scented stock, or possibly a fragrant form of nicotiana. Another fragrant flower to try would be one of the fragrant petunias such as one from the "Daddy" series. Although these would prefer more light they might still bloom for you and they are fragrant, especially at night.
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