The indoor cactus plant is said to be near impossible to kill, presumably because of their harsh desert roots.
Unfortunately, if you care for indoor cacti as you do other houseplants, your cacti are most likely doomed to failure…
Indeed, You will be sentencing them to a premature death.
Once you understand their needs,however, your indoor cacti will thrive.
Water cacti when the top 1/2 inch of the growing medium is dry to the touch. Soak the medium thoroughly and allow it to drain when watering. You do not leave the cacti constantly sitting in a dish of water, as this encourages rot. Feed cacti from spring to fall with 5-10-10 fertilizer every two to three months, but do not feed immediately after transplantation.
Things You Will Need
Peat moss (optional)
Garden soil (optional)
Cactus potting mix (optional)
Pot a desert cactus in a mix of 1 part peat moss, 1 part garden soil and 1 part sand, or a prepackaged mix designed specifically for cacti. Transplant in the spring after the cactus has grown within 1/4 inch of the sides of the pot, but don’t allow it too much extra space, the next pot size up will be adequate.
Place indoor cacti in a window facing south, if possible. Choose an east- or west-facing window otherwise. Supplement with additional bright light for a total of 12 to 18 hours a day during the cacti’s growing season to encourage flowering.
Maintain a relative humidity of 10 percent to 30 percent and a temperature between 65 and 90 degrees Fahrenheit. Remember, glass windows with the direct sun can get extremely warm, so keep a thermometer nearby. A hygrometer will help you keep tabs on humidity.
Move cacti to a location where the temperature ranges from 45 to 55 so they can go dormant for the winter. Water sparingly and from the bottom, just often enough to keep the plants from shriveling. In fact, even watering once a week may be excessive, depending on the plant and growing medium. Stop feeding cacti during their dormant period.
Every cactus is a succulent…
Every succulent is not a cactus.
“Cacti” and “Succulent” are general terms. Cacti belong to a specific family of plants, but the species within that family come from some very different habitats.
Many cacti, such as those in the genus Ferocactus, are in fact true desert dwellers. Others, such as those in the genus Echinopsis, live in the grasslands of South America, those in the genus Oreocereus live in the high Andes mountains, and those in the genus Epiphyllum live in jungles and don’t even live in the ground, but upon other plants.
Watch for flower buds to form and monitor the moisture level of the cacti’s growing medium. When water uptake increases and buds are developing, the plant is no longer dormant and will need to be provided with care appropriate for the growing season.
Old-hand gardeners know for best success indoor cactus and succulent plants require a certain amount of neglect.