We call it the witching hour when the setting sun backlights my enormous cactus garden in the California desert. As the sun sets, it illuminates the cactus so each plant has its own aura of thousands of glowing spines.
Although most folks can’t grow monumental cacti like we do in the desert, there’s another way to get the same effect in your home or apartment.
A potted cactus in a west-facing window will create it in miniature. It’s more pronounced in the winter on south facing windows when the sun is low in the sky all day. While these spiny succulents are curiously beautiful, they’re so easy to grow that every black thumb gardener will find success.
To take advantage of winter light it’s important to know what forms of cacti work best with winter sun. Those with a lot of densely packed spines are the best for backlighting. Those with colored spines, usually red or gold, offer the brightest color.
Another technique is to use cactus to create a bold silhouette. For these I prefer those cacti with monstrose forms. These are curious versions of ordinary cactus that become strangely shaped by a phenomenon unique to succulent plants. The single growing point fans out or becomes wavy to create a distorted yet beautiful form.
Start with an interesting container. This is an opportunity to shop local by supporting ceramic artists in your town, which keeps your dollars in the community. Another low-cost option is to create your own uniquely decorated pots. Start with a simple terra cotta pot, then upcycle it with mosaic, painted textures or decoupage accents. Rusted food tins or upcycled tin cans are cheap, easy to get and fit nicely into rustic or organic-style homes.
Next find a cactus suited to the pot. Cacti don’t need a big root zone because they hold moisture inside their bodies for a long time. That’s why they’re often grown in shallow dish or bowl shaped planting pots. More exposed surface soil makes it easier for the roots to take up moisture when it’s applied. During winter when nearly all cacti are dormant, these plants go many months without any watering at all.
Use special potting soil designated for cacti. If it’s not available, mix ordinary potting soil with equal amounts of sharp sand to ensure rapid drainage. Avoid using a saucer since these are responsible for killing more cactus than any other cause. You want the moisture to travel through and out the bottom quickly, so water and then leave them on the sink to drain for a few hours. Use a piece of tile or a coaster to protect your table top.
The soil line at the base of each cactus is the most vulnerable part of these plants. This is the point where the cactus skin yields to the hard root crown. When water is allowed to stand against the cactus skin, there’s a much greater chance of rot being introduced to those cells. That’s why it’s far safer to plant them on the high side and risk some root exposure than take a chance on too deep a position that may eventually kill it. Decorative gravel is better for this transition zone because it won’t retain moisture there.
To finish off your potted cactus, select the right color fine gravel to cover up the potting soil. The best source is aquarium gravel because it’s non-toxic and won’t hurt fish so it’ll be fine for a cactus. You’ll find it at most pet stores. Choose natural colored gravel for a minimalist or organic look. Play with fun modern ideas by experimenting with vivid colored gravel, or turn it into a fun children’s project.
Whether you’re creating gifts or simply buying potted cactus for your home, always remember this backlighting trick. It adds a whole new dimension to indoor cultivation of these spiny plants. Dive in this winter to start your own indoor cactus garden with these natives of the Americas. Though they are often passed over in favor of less prickly succulents from Africa, you’ll be rewarded with the finest flowers in the entire succulent kingdom.