Opuntia ficus-indica, the most widely cultivated species of prickly pear cactus, in fruit (the pears are orange) at Walnut Creek&#8217;s Ruth Bancroft
Opuntia ficus-indica, the most widely cultivated species of prickly pear cactus, in fruit (the pears are orange) at Walnut Creek's Ruth Bancroft Garden. (Brian Kemble)


Q We have a large, old (probably about 40 years old) cactus in our yard that has produced many wonderful prickly pears every year. The plant is about 12 feet high and about 8 feet across with very mature pads. Little new growth appeared this year, and we harvested only two prickly pears (birds got the other two), so we had a grand total of four pears. Last year, I think we had about eight. In previous years, though, the cactus produced dozens of gorgeous, delicious fruits -- ours have the red-orange flesh, not the rosy-red found in stores. Would trimming back the plant help?

A Most of the fruit on a prickly pear comes on newer pads, so little new growth would result in diminishing fruit production. Cutting back the plant back would cause new growth and might lead to more fruit production, not to mention more accessible fruit. However, this does not answer the question of why there has been so little fruit lately. Twelve feet tall is enormous, and a prickly pear of this size should have lots of fruit. You might try adding compost and manure to the area around the cactus, in case soil fertility has declined.

Prickly pears come in various colors. At maturity, they could be yellow, orange, red, purple or pink. The colorful fruit gives these plants two seasons of color: the first one in the spring, when they come into flower, and the second one in the fall, when the fruit ripens. The red-orange color of your fruit suggests that it is probably Opuntia ficus-indica, the most widely cultivated species.

At the Ruth Bancroft Garden, we have both red-fruited and orange-fruited selections of this species, and both are tasty. For those who have not had previous experience with prickly pears, it is important to note that they must be despined before being eaten. They can be handled with tongs until this is done.

Q In your column, it said that all cactus plants originated in the Americas, but I heard there was one kind found in Africa and Madagascar. Is this correct?

A It is true that there is one epiphytic cactus (that is, a cactus which grows in trees rather than in the ground) that occurs in tropical Africa, Madagascar and Sri Lanka as well as in the American tropics. Its slender, rope-like stems hang down from tree branches, and its small flowers are whitish. This plant is named Rhipsalis baccifera, but it is not often cultivated because its flowers are not showy like so many other types of cactus. Botanists presume this species was carried by birds eastward across the Atlantic to Africa, then onward to Madagascar and Sri Lanka.

Email questions on drought-resistant plants to info@ruthbancroftgarden.org.