Wouldn’t You Like to Know More About…
…our Friendly Neighbors, the Saguaro Cacti?!
The magnificent Saguaro Cactus, the state flower of Arizona, is composed of a tall, thick, fluted, columnar stem, 18 to 24 inches in diameter, often with several large branches (arms) curving upward in the most distinctive conformation of all Southwestern cacti. By the way, the name saguaro” comes from the Indian word “sah-wa-ro.”
The skin is smooth and waxy, the trunk and stems have stout, 2-inch spines clustered on their ribs. When water is absorbed , the outer pulp of the Saguaro can expand like an accordion, increasing the diameter of the stem and, in this way, can increase its weight by up to a ton.
The Saguaro often begins life in the shelter of a “nurse” tree or shrub which can provide a shaded, moister habitat for the germination of life. The Saguaro grows very slowly — perhaps an inch a year — but to a great height, 15 to 50 feet. The largest plants, with more than 5 arms, are estimated to be 200 years old. An average old Saguaro would have 5 arms and be about 30 feet tall.
The slow growth and great capacity of the Saguaro to store water allow it to flower every year, regardless of rainfall. The night-blooming flowers, about 3 inches wide, have many creamy-white petals around a tube about 4 inches long. Like most cactus, the buds appear on the southeastern exposure of stem tips, and flowers may completely encircle stems in a good year.
A dense group of yellow stamens forms a circle at the top of the tube; the Saguaro has more stamens per flower than any other desert cactus. A sweet nectar accumulates in the bottom of this tube. The Saguaro can only be fertilized by cross-pollination — pollen from a different cactus. The sweet nectar, together with the color of the flower, attracts birds, bats and insects, which in acquiring the nectar, pollinate the Saguaro flower.
Unlike the Queen of the Night cactus, not all of the flowers on a single Saguaro bloom at the same time. Instead, over a period of a month or more, only a few of the up to 200 flowers open each night, secreting nectar into their tubes, and awaiting pollination. These flowers close about noon the following day, never to open again. If fertilization has occurred, fruit will begin to form immediately.
While the Whitewing Dove (whose northern range coincides with range of the Saguaro) is one of its primary pollinators, it is the Gila Woodpecker and the Gilded Flicker who make their home in the Saguaro Cactus by chiseling out small holes in the trunk.
Growing Your Own
You can buy saguaro seeds and they need to be potted in a mixture of potting mix and sand. The seeds need to be planted very shallowly. Spray the pot with water rather than water it and keep it out of direct sunshine.
The first indication of growth will be a few spines sticking out of the soil. After a year you might have a plant an inch tall. Over ten years you will see a miniature cactus develop and grow to about 6 inches in height. After 35 years it might start to bloom and after 75 years it might start to develop arms.
Buying one Ready to Plant
If you want a saguaro that looks like a cactus and has some presence, you will have to buy one. Because of the length of time taken for a seedling to develop a saguaro cactus is quite an investment.
Enormous Weight
A mature saguaro can weigh several tons and need special handling for successful transplantation. You will need to have a good soil enriched with a potting mix. Depending on the height of the saguaro you buy. For a small 10 foot plant, you need a hole at least 18 inches deep. The width of the hole only needs to be enough to take the cactus because the root system is very shallow.
Watering
Although the cactus does grow in very arid conditions it is important to water it well in the first few years. Apart from that it needs hardly any attention at all. You will not see a great deal of growth but if your cactus is over 35 years old, you can hope to see it blossom.

