First Congratulations on your bulb lasagna display. You can cut the stems near the base of each faded flowers as soon as the bloom is over but if you want these potted bulbs to flower next year you need to let the leaves mature and turn yellow. This is when the bulb is making next years's flowers. Once the leaves are easy to pull away and have no more green color you can tidy up and remove all that dead foliage. You can add summer flowers to the container that held the bulbs but because you have to wait for the foliage to fade and because the bulbs under the soil like to dry out in the summer you need to chose plants that like dry soil if you want blooms again next spring. Lavender or sedums are both good choices. Try to water very little during the summer and fall months. A more practical option is to dig up the bulbs with leaves still intact right after they finish blooming.  Carefully store the bulbs in a shaded spot outdoors sitting in nursery pots or another container that has good drainage. This way the leaves can ripen and yellow over the next 6 weeks.   In the fall you can replant these same bulbs or for less work and more dependable blooms buy fresh bulbs in the spring for your pots and replant the old bulbs into the garden. Tulips rarely return to bloom as well the second year in a bulb lasagna but daffodils and small bulbs such as crocus can be used for several years. Keep growing, Marianne Binetti