Protect Your Dog from Toxic Plants: Safety Tips Dog Training Elite Worcester Ethane Cracker Plants: What Are They? The Climate Reality Project Blue Vervain (Verbena hastata) is a native perennial and biennial species with a high pollinator value. In summer or early fall, it blooms pencil flower spikes full of blue violet flowers. Blue Vervain Close up of Chinese grass or Rami (Boehmeria nivea), a plant in the Urticaceae family, growing in China Stock Photo Alamy Boskke (@boskke) London