Bulbs (Spring & Fall)

Flowering bulbs — including tulips, daffodils, crocus, hyacinths, alliums, and lilies — are self-contained nutrient packages that store the energy for next year's bloom in their modified underground stems. This unique biology means fertilization strategy is fundamentally different from most garden plants: the critical feeding window is after bloom, not before it, because that is when the foliage is manufacturing the carbohydrates that recharge the bulb for the following season. The single biggest nutritional mistake gardeners make is cutting back bulb foliage immediately after flowers fade — those yellowing leaves are the solar panels powering next year's show. Phosphorus and potassium are the most important nutrients for bulbs because they directly support root development and carbohydrate storage in the bulb structure. Nitrogen is needed in smaller amounts and primarily supports leaf growth during the post-bloom recharging period. At planting time, bone meal has been the traditional amendment mixed into the planting hole, though modern formulations like bulb-specific 9-9-6 blends often provide more balanced nutrition. Spring-planted summer bulbs (dahlias, gladiolus, cannas) have different needs than fall-planted hardy bulbs — they benefit from regular feeding throughout their growing season similar to annuals. For perennializing bulbs (those you expect to return and multiply year after year), an annual topdressing of balanced fertilizer in early spring as shoots emerge and again after bloom fades provides the nutrition needed for reliable long-term performance in the garden.