The tulip is the great mixer of any garden. Since they're available in all colors of the rainbow except blue, tulips are a great way to paint your garden canvas. Mix them in with annuals or perennials, making sure to put shorter plants in the foreground. Tulip varieties range from short to very tall, and all are fit for cutting. In October or November, plant bulbs in a sunny spot that gets good drainage. (If you experience mild winters where you live, December may also be an acceptable time to plant.) Plant bulbs 4 inches (10 centimeters) deep for shorter varieties and about 8 inches (20 centimeters) deep for taller types. Always face the flat side of the bulb down.