Fertilizer for Lilies: NPK Guide and Application Rates
Lilies benefit from spring and post-bloom fertilization to sustain bulb health and flower quality year after year. The University of Minnesota Extension recommends applying a balanced fertilizer when shoots emerge in spring, then switching to a low-nitrogen bloom formula as buds develop. Fertilizing after flowering is equally important, as this is when the bulb replenishes its energy reserves for the following season.
Quick Reference
What NPK Ratio is Best for Lilies?
The recommended NPK ratio for lilies is 5-10-10. The phosphorus-heavy 5-10-10 ratio supports strong root systems and flower/fruit production in lilies.
Lilies NPK needs shift at each growth stage. Balanced formula for new bulb shoots emerging in spring during the Seedling phase, then phosphorus and potassium for large, vibrant blooms once flowering begins.
NPK by Growth Stage for Lilies
| Growth Stage | NPK Ratio | Notes |
|---|---|---|
| Seedling | 10N 10P 10K N 10% Nitrogen: leaf and stem growth P 10% Phosphorus: roots and flowers K 10% Potassium: health and disease resistance Learn more about NPK | Balanced formula for new bulb shoots emerging in spring |
| Vegetative | 10N 10P 10K N 10% Nitrogen: leaf and stem growth P 10% Phosphorus: roots and flowers K 10% Potassium: health and disease resistance Learn more about NPK | Support stem elongation and leaf development |
| Flowering | 5N 10P 10K N 5% Nitrogen: leaf and stem growth P 10% Phosphorus: roots and flowers K 10% Potassium: health and disease resistance Learn more about NPK | Phosphorus and potassium for large, vibrant blooms |
| Fruiting | 5N 10P 10K N 5% Nitrogen: leaf and stem growth P 10% Phosphorus: roots and flowers K 10% Potassium: health and disease resistance Learn more about NPK | Feed after flowering to help bulbs store energy |
When Should You Fertilize Lilies?
In zone 3, start fertilizing lilies in May. In zone 9, begin as early as February. Apply every 4 weeks through the growing season.
Which Zones Can Grow Lilies?
Lilies grows in USDA zones 3 through 9, spanning a 7-zone range.
Fertilization Start by Zone
| Zone | Start Month |
|---|---|
| Zone 3 | May |
| Zone 4 | April |
| Zone 5 | April |
| Zone 6 | March |
| Zone 7 | March |
| Zone 8 | March |
| Zone 9 | February |
What Are the Best Fertilizer Products for Lilies?
Look for products with an NPK close to 5-10-10. Espoma Bulb-tone is the most popular choice among home gardeners for lilies.
- Espoma Bulb-tone
- Jobe's Bulb Fertilizer
- 5-10-10
Prices vary by retailer and region. Check current pricing before purchasing.
Container and Raised Bed Adjustments for Lilies
Grow in 8+ gallon containers with excellent drainage; feed every 3 weeks with liquid fertilizer
Common Fertilizing Mistakes with Lilies
- Cutting back foliage immediately after flowering, starving the bulb of resources for next year.
- Over-fertilizing with nitrogen, which produces tall, weak stems prone to toppling.
- Failing to feed after bloom, which is the most important feeding period for bulb regeneration.
- Planting in soggy soil; lilies require excellent drainage regardless of fertility level.
Tips for Fertilizing Lilies
- Apply balanced fertilizer when lily shoots are 6 inches tall in spring.
- Continue feeding for 4-6 weeks after blooming to help bulbs store energy for next year.
- Incorporate bone meal at planting time for slow-release phosphorus throughout the growing season.
- Do not remove foliage until it yellows naturally; leaves manufacture food for the bulb.
Organic Fertilizer Alternatives for Lilies
Sources
Source:Clemson University ExtensionLast updated: