Bee balm is the native wildflower of the cutting garden - shaggy, brilliant scarlet (or pink, lavender, or white) flowers that attract hummingbirds and are worked constantly by bumblebees. It spreads by underground stolons and will colonise if not divided regularly, but that vigour makes it one of the most productive perennials you can grow. The foliage is scented - strongly of bergamot - and the whole plant is used in tea.
Cut when the first florets in the crown are opening; the flower continues to open progressively and the whorled structure is attractive at all stages. Powdery mildew is the perennial challenge - give plants adequate spacing and good air circulation, and choose resistant cultivars like 'Jacob Cline' or 'Raspberry Wine'.
Ecoregions:Northern ForestsEastern Temperate Forests
Powdery mildew
White or grey powdery coating on leaves - usually starting on older growth in humid conditions or when nights cool.
Improve air circulation by thinning plants. Apply neem oil or potassium bicarbonate spray at first sign. Avoid overhead watering.
The white bloom on the leaves
The zinnias are wearing a grey-white dust that wipes off under a finger, and the instinct to reach for a spray is almost always the wrong one to reach for first.
What to cut in September, and what to leave alone
The instinct to tidy every border in September is mostly wrong - some of what looks finished is still feeding the plant, and some of it is feeding something else entirely.