Barrel cactus require lots of sunlight, well drained soil and little water. Apply minimal fertilizers to the growing season only once annually with low-nitrogen cactus-type fertilizer. Prune off all dead and rotted, and shelter against excessive frost, because a long period of frozen leaves is destructive to the plant. There are few pests but look out for mealybugs and scale insects. Cacti that are grown in containers might need repotting after every few years, preferably during spring. A Barrel Cactus would be a very dramatic desert accent and would live decades with the correct amount of sun, water, and protection.