Sempervivum "Gold Rush" is a striking succulent that forms mounds from thick, fleshy, brightly colored leaves of red-red and golden. Fertilizing: This Sempervivum grows well without feeding, but it benefits from a controlled-release fertilizer at the beginning of the growing season. However, it is important to remember that fertilizer needs and how long they are used will depend on the season as well as the fertilizer purchased. Make your own cactus potting mixture or use a commercial mix.