Grow a mini cactus in a pot indoors for a low-maintenance, hardy houseplant. The plants require very little care to thrive. As long as they get lots of sun and are in a well-draining environment, mini cacti grow happily for years.
Proper potting is important in growing a healthy plant. The right potting soil and the care right after planting are critical for success. You can put your potted mini cactus outside in summer, but be sure to bring it in before winter weather sets in since cactus plants tend to be frost-tender.
Step 1: Choose a Pot
Select a pot that's 1 inch larger than the root mass or the nursery pot the mini cactus is currently in. Make sure the pot has at least one drain hole in the bottom to prevent excess water from accumulating around the roots. Mini cacti grow well in 2- to 4-inch pots depending on the original size.
Step 2: Fill the Pot
Spread a 1/4- to 1/2-inch layer of fine gravel in the bottom of the pot. Add a commercial potting soil formulated for cacti and succulents, which provides proper drainage for cacti. Regular potting soil holds too much moisture for a cactus.
Step 3: Remove Cactus From Nursery Pot
Slip the mini cactus out of the nursery pot. Wear gloves to protect your hands from the sharp thorns. If the pot doesn't slip off the roots easily, give it a gentle squeeze to loosen the soil.
Step 4: Plant Mini Cactus in Pot
Place the mini cactus upright in the new pot. Hold it with the base of the stem 1/4 inch below the lip of the pot. Add more soil under the roots if you need to until the cactus sits on its own in the pot. Fill in around the root ball and gently press the soil down with your fingertips.
Step 5: Choose a Sunny Spot
Place the pot in a sunny spot after planting. Wait to water the cactus for two full weeks after you pot the mini cactus. The disturbed roots establish themselves better if they're left dry for a two-week period after planting.
Step 6: Water the Mini Cactus
Water your mini cactus once a month in winter and twice a month in spring, summer and early fall. Place the pot in the sink and run water over it until the liquid starts to drip out the drain holes in the bottom of the pot. Let the pot drain and then place it in a sunny window or outside in hot weather. You can place your mini cactus on a tray to protect your furniture, but be sure to empty any water that builds up to prevent the roots from rotting.
Step 7: Fertilize Mini Cactus Regularly
Fertilize mini cacti every other month in spring and summer. Select a 5-10-10 fertilizer and apply it according to the manufacturer's instructions. Water well after fertilizing.
Step 8: Repot Only When Necessary
Move your mini cactus to a slightly larger pot once the roots fill up the current pot. Avoid increasing the pot size too rapidly. Pots more than 1 inch larger than the root mass hold too much moisture in the soil, potentially leading to overwatering and root rot.
Eulalia Palomo has been a professional writer since 2009. Prior to taking up writing full time she has worked as a landscape artist and organic gardener. Palomo holds a Bachelor of Arts in liberal studies from Boston University. She travels widely and has spent over six years living abroad.