Saffron is a rare, expensive spice that comes from the stigmas of crocus flowers, called Crocus sativus. Each lovely purple flower produces only three stigmas, so you must gather many flowers to harvest only a small quantity of the herb, which is often used to flavor paella and other dishes from Asia and the Mediterranean area. The saffron crocus blooms in fall and each bulb produces only one flower, so you must grow 50 to 60 plants to yield one tablespoon of this precious spice.
Prepare your planting area by removing all weeds, grass and any other plants that might compete with the saffron crocus for water and nutrients. If your soil is clay, dig in about a gallon bucket of compost for every square yard of planting area. If your soil is sandy or loamy, you needn't add anything, but do spade the soil to break up any hard clumps of soil and remove any rocks.
Plant saffron crocus in fall by digging holes 3 to 5 inches deep and 6 inches apart. Drop one bulb into each hole and then cover them with the soil you dug out. Firm the soil with your palm and then set a sprinkler or soaker hose on the area for about 15 minutes.
Water your saffron crocus to keep the soil moist but not soggy, especially if your winter rains are infrequent and slight.
Fertilize your saffron crocus once each year with a balanced fertilizer with an N-P-K ratio of 16-16-16. Spring is a good time to apply plant food.
Separate your saffron bulbs after several years and replant them as you did when you first began growing this crocus. They divide readily, so in time you will have plenty of saffron crocus bulbs, from which you can harvest the valuable stigmas.