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What NPK Ratio Do Flowering Plants Need?

Penn State Extension

Flowering plants need a phosphorus-rich NPK ratio like 5-10-10, 10-30-20, or 15-30-15 to promote maximum bloom production. Phosphorus (the middle number) drives flower formation and root development. Use balanced fertilizer during establishment, then switch to bloom-boosting formula once plants are ready to flower. Scotts Super Bloom (12-55-6) and Miracle-Gro Bloom Booster (15-30-15) are popular choices.

What You Need to Know

Flowering plants need a phosphorus-rich NPK ratio like 5-10-10, 10-30-20, or 15-30-15 to promote maximum bloom production. Phosphorus (the middle number) drives flower formation and root development. Use balanced fertilizer during establishment, then switch to bloom-boosting formula once plants are ready to flower

Scotts Super Bloom (12-55-6) and Miracle-Gro Bloom Booster (15-30-15) are popular choices.

For personalized recommendations based on your specific garden size and fertilizer, use our fertilizer calculator.

Sources

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