Amethyst improved basil

Amethyst Improved is the purple Genovese — Gardening Know How calls it the only purple Genovese basil cultivar, which is the whole point of it. Where Dark Opal and Purple Ruffles carry narrow or crinkled leaves and a reputation for bolting fast, Amethyst Improved has the broad, thick, downward-cupped leaf of an Italian pesto basil in a colour so dark it reads as near-black, with only a ghost of green sometimes showing at the margins. Johnny's lists those leaves at 2-3 in long on 16-20 in plants. Growers pick it because it holds in the field roughly as long as a green Genovese type rather than running to seed in midsummer heat, so purple leaf is available for a usable harvest window instead of a few weeks. It also flowers purple with red bracts, giving it a second life as garnish and bouquet material once it does bolt.