Daffodils are spring blooming bulbs that need a cold dormancy in order to grow and thrive. They are typically planted in the fall in United States Department of Agriculture plant hardiness zones 4 to 9. The bulbs then grow fleshy roots and become established before the winter chill. If you just found or acquired some daffodil bulbs in February, you missed their ideal planting time, but it's not too late. Get your coat on and plant your daffodil bulbs as soon as possible.
Examine the bulbs to check that they still look healthy. They should be firm and plump, not rotting or shriveling. Discard the bulbs that do not look healthy.
Check your planting bed. If it is frozen and unworkable, you have no choice but to wait to plant your bulbs outdoors. In the meantime, store them in a paper bag in the refrigerator (in a separate area than fruit) and plant them outdoors when the ground is workable again. Alternatively, plant daffodils indoors in pots after six weeks in the refrigerator (they need a chilling period to grow).
Work the soil outdoors to a depth of about 10 to 12 inches. A hoe or garden tiller will be easier to use than a garden fork in February when the ground is most likely still hard from the winter freeze.
Improve the soil. According to the University of Missouri, incorporate 2 to 3 pounds of fertilizer with a N-P-K ratio of 1:4:4 or 1:3:3, such as one labeled 6-24-24, for every 100 square feet. If your soil is heavy in clay, also mix in equal parts of course sand and organic matter (e.g., compost, leaf mold) that total about 4 to 5 inches. In sandy soil, mix in 4 to 5 inches of organic matter.
Plant the daffodils so their bases are 6 inches deep (tips are facing up) and space them 6 to 12 inches apart. The closer you plant them together, the sooner they will fill in the space and the sooner you will have to dig them up and divide them.
Backfill the soil and pack it down lightly. If the soil is dry when planting, water them with about an inch of water.
Add about 3 inches of mulch (e.g., pine needles, wood chips) to help keep the soil cool as long as possible before spring arrives. Remember, daffodils need a cold period to grow.