Cacti are a diverse group of plants comprised of 127 genera and about 1,750 known species. The majority are native to North and South America, with few exceptions. While you may think they only live in deserts, some plants live in forests, coastal areas, and even mountains. Water loss is a typical environmental challenge. Understanding how they cope can give you insights into their care.
Adaptations for Life on the Warm Side
The two most noticeable features of cacti are their spines and fleshy pads. The former minimizes water loss as modified leaves. The latter allows them to store water. Gas exchange occurs at night instead of during the day, like most plants. That also helps cacti retain moisture. Therefore, you shouldn’t overwater plants in cold climates to prevent rotting.
It may seem counterintuitive, but cacti are shallow-rooted. Again, they will do best in well-draining soils to avoid mold and rot. You can keep in-ground cacti in raised beds to improve drainage. Container plants will thrive in clay pots with holes on the bottom for excess water. These conditions are imperative for your cacti to survive, no matter how cold it is outside.
Outdoor Cacti Care
Some species can survive colder conditions. Plants, such as the Prickly-Pear Cactus and Missouri Pincushion, can live even in USDA Hardiness Zone 4. These plants are native to these the Midwest. You’ll find them growing in the wild in shrublands and prairies.
However, the site location is vital for your landscaping. These plants will fare well in rock gardens that will minimize frost heaving. The cycle of freezing and thawing can wreak havoc on any plant. Another excellent choice for cacti is on a slope, which will also help with drainage. However, avoid places in direct sunlight. Opt for indirect light instead.
Your cacti should go into the winter fat. That means fertilizing them in late summer but not too close to the first frost. If you get a lot of snow in your area, you can also cover them with burlap. The material will prevent broken limbs and other damage. We suggest watering your plants less frequently leading up to the colder months. That will encourage your cacti to go dormant, better for overwintering.
Indoor Cacti Care
Many species, such as the Barrel Cactus, are easy to grow indoors if your climate is too cold. However, it’s essential not to go to the other extreme just because they are inside. We recommend keeping your plants away from heating vents. Also, avoid putting them in direct sunlight. They can still get sunburn in your home.
The shorter days will encourage your cacti to go dormant. You can water them less frequently until spring when the conditions warm up again. It’s also an excellent time to fertilize them.
Even though cacti are usually warm-weather plants, some are cold-hardy and can survive winter. It’s critical to prepare your outdoor plants for the weather change. Fortunately, the survival instinct runs strong in cacti when given the proper care.