Place half of the rocks (included) in the bottom of the terrarium to act as a drainage layer. In a separate bowl, dissolve growing medium pellet in 3/4 cup of water, fluff with fork, and place into terrarium. Sow creeping thyme seeds 1/8" deep and lightly cover with growing medium; sow alyssum and lobelia seeds directly onto the surface of the growing medium, gently press in, and do not cover - these seeds need light to germinate. Place in a warm, bright location with ample air circulation; keep growing medium moist but not overwatered. Days to germinate: creeping thyme: 14-21 days, alyssum: 7-14 days, lobelia: 21-30 days. Once seedlings develop their second set of leaves, begin watering with balanced plant fertilizer mixed at half-strength.
Save the second half of the rocks to personalize your fragrant flower terrarium! After your seeds have germinated, place rocks around the plants to add your own special decorative touch.