The phrase "was in flower" is commonly used to describe plants that are in bloom. However, there are numerous synonyms and alternative expressions that can be used instead, depending on the context. Some of these might include "in full bloom," "at the peak of flowering," "bursting with color," "covered in blossoms," "showing off its blooms," "displaying its flowers," "flowering profusely," or "laden with blossoms." These synonyms not only add variety to your language but also help you to better describe the beauty and abundance of flowers, creating a more vivid and engaging picture for your readers or listeners.