Blood Meal vs. Bone Meal for Irises and Lilies: Different Nutrients, Different Jobs

Blood meal and bone meal are not interchangeable. They supply different primary nutrients for different growth phases.

Blood Meal = Nitrogen (N)

• Stimulates green, leafy growth.
• Sources: blood meal, cottonseed meal, alfalfa meal, fish meal, fish emulsion.
• Not alkaline; pH neutral to slightly acidic.
• Use: Early season, heavy feeders, compost activator.

Bone Meal = Phosphorus (P)

• Stimulates root development, flower/bud formation, seed set.
• Sources: bone meal, soft rock phosphate.
• Deficiency signs: purple leaves, brittle roots, skinny stems, late maturity.
• Essential for all bulbs, rhizomes, and tubers at planting.

For Irises (Rhizomes) & Lilies (Bulbs)

• At planting: Bone meal in the hole — feeds roots and future flowers.
• Early spring: Light blood meal or fish emulsion if foliage is pale.
• After bloom: Bone meal again to rebuild bulb/rhizome.

Key Takeaway

Nitrogen grows leaves. Phosphorus grows roots and flowers. Use both, but at the right times. Visit avant-gardening.com for more on organic fertilizing.