Gil, yes its important, you want to let them die down naturally, so the nutrients from the leaves can replenish the bulb. Otherwise they will have puny blooms or no blooms at all. You also want to deadhead the spent blooms so that they don't spend energy away from the bulb to produce seed. Although let the species be, they will self-seed and naturalize.

Sharon

Thanks Sharon, I did know it was important, I just didn't know what would happen if someone did cut the leaves off.

I will tell her to buy some bulb boost fertilizer next year and leave the leaves alone, and maybe the tulips will recover by the following year.

After my tulips are done blooming,I always rip the leaves off. I've been doing this for 16yrs. They were planted by the previous owner. These red tulips aren't my favorite plant and I figured that I'd kill them by doing this, but my patch keeps on growing. I fertilize this bed weekly in the summer, maybe that's enough to keep them going.

After the tulips are done blooming you can braid the leaves to help hide them with your annuals, also the leaves are still attached to the bulbs to give them the food they need till they dry up and then give a gentle turn and pull the leaves separate from the bulb very easily and does not harm the bulb Happy Blooming

Since you all know a lot more about tulips then I do, I have a question that sort of goes along with this. What if I was sent tulips and I trimmed all of the leaves off before they went in the vase... I know nothing about flowers but i thought that was what you were supposed to do, now I'm worried that they might die before they bloom. What do you think?

This thread is about tulips that are planted in the ground. I don't think it makes any difference if you trim the leaves from tulips that have been cut.