Succulents and cacti require bright, direct sunlight to thrive. Place your terrarium in a south or west-facing window to ensure it receives enough light. If your home doesn’t get enough sunlight, you can supplement with grow lights.
Overwatering is the biggest danger for succulents and cacti. In the hot and dry climate of Phoenix, it’s important to be careful when watering. Check the soil or sand regularly and only water when it’s completely dry. When watering, water thoroughly and allow the excess water to drain out of the bottom of the terrarium. Do not let the terrarium sit in standing water.
For a soil terrarium, disperse water evenly across the top until soil is saturated through. For a sand terrarium, use a syringe, dropper, or turkey baster to evenly squeeze the water to the roots of the plant until the underlying soil is saturated.
During the growing season — spring and summer — you can fertilize your succulents and cacti with a cactus or succulent-specific fertilizer or worm castings once a month.
If your succulents or cacti become leggy or overgrown, you can prune them back. Use a clean pair of scissors or shears to make a clean cut at the base of the stem.
Succulents and cacti are adapted to thrive in hot and dry environments.. however, they do not do well in extreme temperatures, especially below freezing. Keep your terrarium in a temperature-controlled room, away from any cold drafts or extreme heat sources.
Watch out for pests like mealybugs and spider mites, which can infest succulents and cacti. If you notice any signs of infestation, isolate the affected plant and treat it with an insecticidal soap.