My colleague, Brent Green and I, studied horticulture at Cal Poly, San Luis Obispo; which is exactly half way between his hometown, Beverly Hills and my hometown, here. We regularly exchanged plant species which were common to one, but rare to the other. One particular plant was a Cereus cactus which Brent had given me when it was not so healthy. When Brent visited the following year, the cactus was healthy enough to return home, where it bloomed profusely. By the time I visited Brent the following year, the cactus had gone into decline and came home with me for proper care. It eventually made the trip several times, like migration, before it finally settled into Brent’s garden. Brent says it blooms at his home because it is happier. Although I have never seen it bloom, it always came here to recover and I Cereusly believe it was much happier in my garden.

True cactus of the family Cactaceae are very useful ornamentals comprising much of the group known as succulents. Succulents are any plant species which stores water in thick, watery leaves or stems. Most are drought tolerant. Many other succulents are of families which are more closely related to poinsettias or lilies.

Unlike other succulents which are endemic to many other continents, cactus only naturally inhabit North and South America. Their “succulent” parts are actually modified stems which may be cylindrical or flat “pads”. The surfaces of these stems are green and perform photosynthesis; which is very important to plants which have no leaves. The leaves are not totally absent, however. They have been modified into the spines or “fuzz” which cover cactus to protect them from grazing animals. The tufts from which the spines protrude are modified buds; which often include one or more larger spines which are actually another type of modified stem. (That is probably more information than you need.)

Flowers are exceptionally impressive and unexpectedly large. Unfortunately, because most commonly used cactus are from desert ecosystems, many bloom at night. Their favorite pollinators, moths and bats are more active at night; and flowers are less likely to desiccate. In milder landscape conditions, night bloomers may stay open during the day. Those which normally bloom during the day usually produce smaller flowers which are very brightly colored. Fruit may also be showy and that of some species is edible.

Structure is variable among the various species of cactus. Many of the most popular only grow to a few inches tall. Some of the larger cactus may get several feet tall. Although unlikely in the Santa Clara Valley, the saguaro cactus grows over forty feet tall in the wild. With very few exceptions, cactus require full sun exposure, very good drainage and minimal irrigation. Too much water can easily kill them. To maximize performance, fertilizer may be applied only in spring and summer.

Although cactus are very tolerant of adverse conditions, they are not for every garden. They are too exotic for many garden enthusiasts, and not compatible with every style of landscape. They usually look best with other cactus or succulents in large groups. There are, of course exceptions; and some of the boldest are excellent for prominent spaces within more traditional landscapes. Cactus are happy in pots so may also be grown on porches, separate from the main landscape.

Because there is so much variability among cactus, it is important for those interested in growing them to research their choices. Their requirements may be very different from anything else in the garden. Handling cactus also requires some ingenuity. I find that the thingy used to move coals in the bar-b-cue is very useful. Certain kitchen utensils may also help; like that other thingy which grabs salad or pasta. It is best to be gentle to avoid breaking spines or bruising stems. Cactus are not as tough as they look.