Answer: Daylilies need full sunshine in order to bloom well so if your plants are getting too much shade, they won't flower well. Or, if they are over-crowded, they may refuse to bloom. You can try separating and replanting in a full sun spot for better performance. The same is true of iris. Daffodils need their foliage to remain intact each year in order to store energy for the following year's floral display. If you cut the foliage down prematurely, it will affect the next year's bloom. You can side-dress your plants with a bloom-boosting fertilizer containing large amounts of potassium (middle number on the fertilizer package) but unless they get adequate sunshine and you leave the foliage alone to die down naturally, they won't bloom well for you.
Hope this information helps you determine just why your plants are not blooming.
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