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How to Fertilize Flower Bulbs

By Jenny Harrington ; Updated September 21, 2017

Spring and summer bulbs add bright color to the garden with a minimum of care needed. Spring bulbs include daffodils, tulips and other varieties. Lily and dahlia are types of summer bulbs. Proper soil conditions contribute to healthy bulb growth each year. Fertilizing the soil adds the necessary nutrients to the bed that the flower bulbs need to flourish. Fertilization at planting gets bulbs off to a healthy start. Amendments added throughout the growing season complete the feeding cycle.

Prepare the bed before planting. Loosen the soil to a 10-inch depth, then work in a 2-inch layer of compost with a spade or hoe. Compost adds organic matter and nutrients to the garden bed.

Apply ½ lb. of super-phosphate fertilizer to every 100 square feet of bulb bed. Work it into the soil to a 10-inch depth so the bulk of the fertilizer sits just beneath the depth where the bulbs will be planted.

Fertilize spring bulbs immediately after flowering with a balanced, 10-10-10 analysis fertilizer. Apply 5 tbsp. per 10 square feet of bed.

Fertilize summer bulbs monthly early in the growing season. Apply 2½ tbsp. of 10-10-10 fertilizer per every 10 square feet each month from the time stems appear until the plants begin flowering.

Apply a final application of fertilizer to all bulbs in fall. Mix 5 tbsp. of 10-10-10 fertilizer with 2 cups bone meal per 10 square feet area. Work this into the soil around the bulbs.


Things You Will Need

  • Compost
  • Super-phosphate fertilizer
  • 10-10-10 analysis fertilizer
  • Bone meal


  • Specially formulated bulb fertilizer can be substituted for general-purpose fertilizer. Follow package instructions for exact application amounts.
  • Water immediately after each fertilizer treatment to wash the nutrients to the root level of the plants. This also rinses any fertilizer off the leaves and prevents burning.


  • Avoid direct contact between the fertilizer and the bulbs. This can cause damage or death to the flowers from fertilizer burn.

About the Author


Jenny Harrington has been a freelance writer since 2006. Her published articles have appeared in various print and online publications. Previously, she owned her own business, selling handmade items online, wholesale and at crafts fairs. Harrington's specialties include small business information, crafting, decorating and gardening.