Answer: These plants tend to begin blooming late in the season but then continue until frost. (They are tropicals and really wait for the warm weather before moving into optimum growth and blooming.) You may find that the slowpokes are in a slightly cooler location or a slightly poorer soil or receive slightly less water than the first to bloom. It is also possible that they were transplanted out too early when the soil was still too cold and are a bit stunted from that experience. You might try a "blossom booster" type of fertilizer if you suspect there is a fertility problem, but apart from that and making sure they are well watered, I suspect patience is the word of the day.
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