Cut Flowers

       
 
I've been playing Hunt the Tulips - here are some I found. No idea how long ago they were planted - 5 years, maybe more. They do seem to be multiplying as even I wouldn't have planted the unopened clump that closely.

As for the cost of growing them for one year only, it probably depends on  why you grow them. If its to sell the flowers, the cost of the bulb and the single tulip it produces in its lifetime has to equal or be less than the amount it would sell for in a bunch of flowers. If its to give pleasure in the garden, its not important and every extra year is a bonus.