Summarize:

Right after planting, the tulips do actually need watering to trigger growth. This will likely be one of the few times you actually have to water them. Do not water them again until you see leaves. Then, you can give them a light sprinkling and that's it. If it hasn't rained in a few weeks in your area, give your tulips a dusting of water. This will be one of the rare occasions when you should step in and get some moisture into the soil. Tulips often need less water during the spring due to lots of rain and moisture. Most of the time, the weather will take care of this plant for you. Normal rainfall is all they need.
Water your tulips once planted. Water developing tulips only during a dry spell.