Yes, Crown of Thorns can be grown indoors. It's a versatile plant that can adapt to indoor conditions as long as it's given enough light (preferably near a south or west-facing window). Ensure the pot has good drainage to avoid root rot, especially if the soil is damp for extended periods. The indoor temperature should ideally be between 65-75°F (18-24°C), but the plant can tolerate temperatures as low as 50°F (10°C).