Jim probably has as much experience planting daffodils as anyone Eric has met. Thus Eric wants to know about planting depth and is there any kind of special soil preparation needed prior to planting these bulbs. Jim explains. The depth for a daffodil is always determined by the size of the bulb. If you have, for example, a 2 inch bulb you would plant it 3 times its depth, or 6 inches. The other consideration is to dig your hole deep enough. Once you do that you don't need to worry too much because daffodils have tactical roots. A lot of people don't understand this. If you plant your daffodil a little too shallow, and one year he did just that, he found they have tactical roots and the root system will pull the bulb to the desired depth it needs for your particular zone, so the next year it will be fine. Daffodils are so easy, deer don't eat daffodils because the daffodil is toxic to deer. They are easy to grow and repeat themselves every year. After about 10 years you may need to divide them.