Long stems shoot upward from the leaves to bloom with small, pretty purple flower spikes. Alpine Betony grows up to 18 to 20 ...

It thrives in cool, moist conditions. Blue vervain is a tall, perennial weed with slender spikes of small, blue to purple ...

From summer to autumn in sub-Saharan Africa, green fields of rice, corn, and other crops are often covered with small purple flowers called Striga. These eye-catching flowers are known as ‘witch ...