How to Fertilize Daylilies for Re-bloom

The daylily (Hemerocallis) has always been the go-to plant for any perennial gardener because of its dependability and beauty. Today, more than 45,000 different varieties of daylilies exist, and new hybrids appear every season. Some varieties of the plant even have the genetic propensity to bloom multiple times throughout the summer. Just because a daylily is genetically inclined to re-bloom, however, does not mean it always will. According to Paradise Gardens, a leader in perennial nursery stock, insufficient fertilization, along with sunlight, rainfall and many other environmental factors, is one of the many reasons daylilies may fail to re-bloom.

Difficulty:

Moderately Easy

Instructions

Things You’ll Need

• 5-lb. bag of agricultural lime
• 5-lb. bag of 13-13-13 or 12-3-6 fertilizer
• 1-lb. bag of ammonium nitrate

1. Prepare the soil. A good feeding program for daylilies should begin before they are even planted in the spring. According to the Alabama Cooperative Extension System, you should perform a soil test four to six weeks before planting to determine your pH and fertility levels. Daylilies grow best when the soil pH is around 6.5. Therefore, if you have a slightly more acidic soil, as many gardeners do, you will want to add agricultural lime to the soil at a rate of 3 to 5 pounds per 100 square feet of space. If your daylilies are already established, do not worry about altering the soil at this point.
2. Fertilize your daylilies. If you have had a soil test done, it should tell you the fertility level of your soil. If you have soil with low fertility level, you will want to spread 2 pounds of 13-13-13 fertilizer per 100 square feet of bed space in the early spring and then again in June. If you have medium- or high-soil fertility, you will only need to fertilize once in the early spring by spreading 2 pounds of 12-3-6 fertilizer per 100 square feet of space.
3. Check your daylilies in the middle of June to see how they are progressing. If they are growing vigorously and have a good green color, you are on the right track. If the daylilies seem to be struggling, apply 1/4 pound of ammonium nitrate per 100 square feet of space as a little boost. The bottom line is that by keeping your daylilies healthy and providing them with enough nutrients, you will have a much better chance of seeing them re-bloom throughout the season.

Tips & Warnings

• Many garden centers perform soil testing or have a variety of do-it-yourself soil test kits available.

• It is best to apply fertilizer when plant foliage is dry. Water thoroughly after fertilization.

• According to the University of Rhode Island Cooperative Extension, slow-release fertilizers are the best kind to use when fertilizing daylilies.

• Always follow all safety instructions when handling fertilizer.