Saffron can cost around $10 per gram or possibly even more than that, but if you have a green thumb, you can grow this rare and expensive spice in your own backyard.

The saffron crocus bulb does not release much pollen and is difficult to find growing in the wild. To grow saffron at home, you'll need to start with bulbs from a trusted source.

Most southern U.S. states offer favorable conditions for growing saffron, and you may be able to grow them in warmer portions of the north. They do best in hardiness zones 6 to 8.

Saffron flowers need lots of sunlight, and it also helps to add organic material to the soil. Be sure the soil is loosened and hill it slightly to encourage good drainage.

Plant your bulbs at the start of fall, and plant no more than about 10 within a square foot of garden space. If you want lots of saffron, dedicate a lot of garden space to it.

The bulbs need at least six inches of water each month to remain healthy. It will take a full year before you see blooms starting to develop, since this is a fall-blooming plant.