Cacti are typically small and compact, making them ideal for windowsills, desktops, and container gardens. Their shapes vary widely, including globular or ball-shaped varieties like Rebutia, columnar and ribbed types such as Echinopsis, and cluster-forming species like Mammillaria. Their colors range from classic green to blue-green, grayish, and even reddish tones. Many cacti feature protective spines, bristles, or woolly tufts, adding texture and character. While they may seem tough and understated, these plants can surprise you with vivid, showy blooms in shades of pink, red, yellow, or white—usually appearing in spring or summer. Though the flowers are often quite large compared to the plant itself, they typically emerge only once the cactus has reached maturity, which can take several years if grown from seed.