When do I feed flower bulbs?
Though bulb companies sell fertilizer at shipping time in the fall and say to add it to holes then, I have to say I never do. The best time to feed bulbs is when they begin active growth, when the green shoots are emerging.
Use an all-natural organic fertilizer, not chemical-based ones; select a formula intended for bulbs. Apply according to label directions. Expert sources like the American Daffodil Society recommend reapplying fertilizer at bloom time as well (again, I feel good if I get the one application on at first sighting of the greens).
After they flower, deadhead the spent flowers only, but let the foliage wither on its own. This is how bulbs feed themselves—so don’t cut off the greens until they die back, at least 6 weeks later.
Quick tip about a bulb you might not have thought of feeding: garlic. Spring’s the time (when the greens are starting to push up into active growth) to feed it, too.