Succulents, and especially cactus plants, usually prefer heat and drought. That’s one reason they make such perfect plants for desert gardens. But in the high deserts or mountains of New Mexico and other Southwestern states, many cacti only can live outdoors in the summer. Enter containers…
Why Plant Cacti in Containers?
The best reason for planting cacti in containers is the flexibility it offers. You can move the plant throughout the year (carefully) to bring it outdoors when summer nights warm and indoors as frost approaches. But you also can move your cacti around to control temperature or sun exposure. Even succulents can burn from intense sun, so it is good to keep an eye on the plants and rotate or move them depending on sun, including sun from a south- or west-facing windows.
Another reason to plant cacti in containers is to isolate watering. When planted outside, especially near drip or other watering systems, cacti can get too much water. With containers, you can control cactus watering based on season and when the plant goes dormant. If you love the look of a cactus in your desert landscape, nothing says it has to be in the ground! If the water or temperature conditions are not ideal, place your cactus outside in a colorful container. Just remember – the outdoor container should have good drainage and can cool off more at night, so don’t leave a container cactus outdoors in winter unless it is hardy to at least 10 degrees cooler than your lowest low.
Finally, most cacti are slow growers, so you don’t’ have to repot them often. Other cacti spread out of control in the garden. You’ve probably seen a xeric yard in your neighborhood with prickly pear growing like a sprawling hedge, maybe onto the sidewalk. It is easier to control cacti when in the confines of a container.
Container Cactus Mix
Planting and caring for cacti in containers is easy, but the soil mix is crucial to success. If you plant a cactus in standard container potting mix, which is designed to help retain water, your cactus roots will get soggy and rot. You can buy special cactus mixes or make your own. Ask friends or local experts for ideas. Examples include adding 1 part coarse sand and 5 parts perlite (for airflow and drainage) to 4 parts of potting mix. Vermiculite also improves aeration but holds too much water. You also can add a little bit of rock dust or pumice to your mix.
Handle your cactus carefully while transplanting. You can use an old sock or towel to wrap around the plant near the base and lift it out of the pot. Or turn the pot with the cactus on its side, resting the plant on an old pillow (that you won’t use again) to cushion the plant while you pull the container off the root ball.
Old long-handled barbecue tongs are great tools for holding a cactus while you place it in its new container; or use regular tongs for smaller plants. The eraser side of a pencil works great for gently pressing soil down around smaller cacti.
Some Favorite Container Cacti
Some of these cacti are spinier than others, so you might want to be careful where you place them. Many will flower, especially in spring or early summer. And some can tolerate pretty cold temperatures, but still would be fun winter houseplants.
Barrel cactus (Echinocactus grusonii). The golden barrel and other barrel cacti are such great landscape plants, giving a pretty round shape to landscape designs. I especially love them on hills. But they’re only hardy to 15 to 17 degrees, so we keep ours in a container.
Pencil cholla (Cylindropuntia leptocaulis). Pencil cholla are pretty scary looking, with spines up to one inch long sticking out from tall, thin branches. They are hardy to -20 degrees and love heat, but spread easily in the yard.
Bishops cap (Astrophytum myriostigma). This is an attractive and slow-growing cactus perfect for a container, especially since it only can handle cold down to 20 degrees. I love the sort of grainy white and green look of the plant. See the second photo above. That is a bishops cap in the middle.
Hedgehog cacti (Echinocereus). It’s native to the U.S. and Engelmanns hedgehog is most common throughout the Southwest. It’s spiny, but should produce bright pink flowers more than two inches across. The plant only reaches about 10 inches in height.
Fence post (Pachycereus maginatus). This is a columnar, almost regal cactus. The columns have ridges with small spines and when planted in a row, they form an excellent wall. Columnar cacti are great choices for planting in containers of homes with high ceilings or to simply provide height behind a grouping of houseplants. They just need plenty of filtered sun.
Ocotillo (Fouquieria splendens). It’s hard to imagine this sprawling cactus in a container, but it can be done. It will need summer heat and can survive temperatures down to 20 below freezing. So, the garden can work, but you can control ocotillo growth in a container and enjoy it as a rising backdrop to other cacti or succulents.
Old man cactus (Cephalocereus senilis). This is by far one of my favorite cacti. But it needs to stay in temperatures above 46 degrees, despite its shaggy layer of “hair.” This is another slow grower, and often a conversation starter in a home!
Spineless prickly pear (Opuntia canacapa). For the look of a gorgeous green and juicy cactus pad and no spines, go with this pretty plant. It still will grow new pads, but you can cut them off or plant them elsewhere. Both regular and hardy prickly pears can survive temperatures down to zero.