Answer: Planting 5 bulbs to a hole wasn't a good idea - if tulip bulbs are overcrowded they will have to compete for moisture and nutrients. As a result they eventually stop blooming, which is your cue to dig and divide them. Tulip bulbs should be planted about 6" apart so their roots have plenty of room to spread. Also, it's important to allow the foliage to die back on its own. The foliage collects and transports energy to the bulbs for the following year's flower display. If you cut the foliage back while it's still green, the bulbs will not have the reserve they need to produce flowers. I'd recommend digging and dividing the bulbs this year and spacing them out. They may not bloom next year but they certainly should bloom the following year.
Best wishes with your tulips!
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