August 17, 2004 > Windowsill Cactus Gardens
Windowsill Cactus Gardens
by Pat Kite
I never meant to start a cactus collection. But I had this outdoor windowsill with an empty sunny space, and I had $1.29 in my purse.
Quick as a gardener's wink, my "red crown" Rebutia minuscula was joined by "rose pincushion" Mammillaria zeilmanniana. When I discovered forgetting to water them was a plus, rather than an "oops," I let an "Old Man Cactus", a.k.a. Espostoa lanata, wave to me. I was hooked, spined, and fuzzed.
There are at least 2,000 cactus or Cactaceae species, and while you can't grow all of them indoors, if you have a truly sunny spot, there are still a plethora of choices. For example, there are at least 150 different types of Mammillaria, including "old lady," "little candles," and "snowball." Blossoms, cream, red, white, or yellow make their grand appearance from March to October. "Red crown" cacti grow to a maximum 3 inches tall, and are ideal for a narrow window ledge. Red to crimson flowers often make a summer coverlet.
The columnar "Old Man Cactus" is a great conversation piece. It looks like Rip Van Winkle standing up, being covered top to bottom with long white hairs. While the hairs seem weird even for a cactus, they make a quite effective blanket that slows down water evaporation. Houseplant size is about 6 inches, and it's a slow grower. The white night-blooming flowers are more apt to appear if the plant is placed on a porch, but may display on occasion.
If you want a prickly cactus rather than a fuzzy one, try "Bunny Ears," or Opuntia microdasys. Butter-yellow flowers charm in spring. Wear gloves for the wicked prickles that are quite practical for the plant but "ouch" on the hands. Prickles on a cactus act as a barrier against desert sun, as well as a predator keep away.
For a non-spine, there's "parson's cap," or Astrophytum myriostigma. I'm mentioning all these fancy Latin names, because when you get to be a cactus collector gourmand, you'll need the names to choose from catalogues. Parson's cap resembles a rounded hat, with some species having a pom-pom on top.
"Peanut" cactus, or Chamaecereus sylvestri, is a particularly good beginner plant. Clustered branches resemble green peanuts covered with soft bristly spines. Flowers are scarlet.
If you have space for a hanging cactus, try "rattail," or Aporocactus flagelliformis. Stems can reach 3 feet long, and red or pink flowers are springtime bonus. Again, you must have sun, about 6 hours per day, or cactus turn wimpy. A windowsill where the sun beats down, and nothing wants to grow, is just ideal.
Cactus soil can be purchased premixed. Otherwise, for desert cactus, use a mixture of one part soil, one part leaf mold, and one part, sharp sand. All containers must have a drainage hole. Water only when the soil feels dry. Shallow spreading roots, unlike the tough plant exterior, are sensitive. Do not water right after repotting. Wait a day. And never over-water unless you want cactus mush.
Nowadays, I always seem to pick up a little cactus whenever visiting a nursery. Just when I think I have enough and then some, a new design beckons. Who can resist? And cacti are a nice gift for friends who claim they have "everything." It's a great no-work hobby.
Cactus Clubs: There is a wonderful Cactus and Succulent Society in San Jose. Look up their next meeting on the Internet at http://www.csssj.org