Spring bulbs push through the soil in early spring, often before the rest of the garden has awoken for the season. Spring perennial bulbs include tulips and daffodils. The bulbs store all the nutrients they need for the following year's bloom over the relatively short period while they are in foliage. Fertilizing the spring bulbs correctly ensures nutrients are available to them when they are fueling up for the following year's flowering season.
Fertilize new bulb beds in fall at planting. Apply a 2-inch layer of compost to the bed and apply 2 pounds of 5-10-10 fertilizer per each 100 square feet of bulb bed. Work the compost and fertilizer in to the top 10 to 12 inches of soil just prior to planting.
Fertilize the bulbs in spring as soon as the first green shoots appear. Apply 1 handful of 5-10-5 analysis fertilizer for each clump of three to five bulbs. Sprinkle the fertilizer onto the soil around the bulbs and turn it into the top 2 to 3 inches of soil with a hand cultivator tool.
Apply half a handful of 5-10-5 fertilizer to each cluster of bulbs every four weeks until the foliage dies back on its own, usually within six weeks of flowering. Water the bed thoroughly after each fertilizer application so the nutrients leach down to the root zone.
Amend the bed in fall six weeks before the first expected frost of the season. Apply 2 tbsp. of bone meal per bulb, sprinkling it around each bulb. Water it in.