How to Grow Roots on Cactus

Put on heavy gloves before working with spiny species of cacti. Tuck the sleeves of your shirt into the wristband of the gloves for additional protection.

Select a cutting appropriate to the species of cactus. Choose 4- to 6-inch segments from the tips of columnar species, select immature pups from globe-shaped species, and choose whole pads from paddle species.

Sever the cutting cleanly with pruning shears or a gardening knife. Make the cut at the junction between two pads of Opuntia cacti, or cut globe cactus pups flush with the ground.

Set the cactus out of direct sunlight in a spot with good air circulation and low humidity. Dry the cactus for several days until the severed end is dry and whitish in color, with a slightly puckered appearance around the edges.

Pot the cactus cutting to half its depth in a 6-inch-diameter plastic pot filled with equal parts coarse sand and perlite. Mound the rooting mixture around the base of heavy cuttings to keep them from toppling over.

Set the potted cactus outdoors where it will receive partial sun and temperatures above 60 degrees Fahrenheit at night and 80 F during the day. Allow no more than one hour of direct sunlight to touch the cactus each day.

Pour 1/4 cup of water onto the coarse sand and perlite mixture five days after you pot the cutting. Add additional water whenever the mixture feels dry at a depth of 2 inches.

Test for roots in three weeks. Grasp the base of the cactus with your gloved hand or a pair of tongs. Carefully attempt to lift the cutting from the pot. Feel for resistance, which indicates root growth.