Answer: You can certainly deadhead. Remove as little foliage as possible when you do so, as this is how the plant maintains its vigor to go on growing and budding later in the season. I am not sure why your plant is flopping over, but you could do a perimeter support system of stakes and string to help keep it off the ground -- this will improve air circulation and help keep the foliage dry which is important in preventing fungal problems. Make sure you are not overfertilizing it as this can contribute to overly long or weak stems, especially in lower light levels. You may find the Endless Summer web site interesting.
Enjoy your plant!
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