After daffodils bloom in the USA, they enter a critical phase where energy is redirected from flowers to bulbs. The leaves continue photosynthesis, producing sugars that are stored in the bulb for next year's growth. Cutting foliage too early weakens the bulb, reducing future blooms. Allow leaves to remain until they turn yellow and wither naturally, typically 6–8 weeks post-bloom.
Daffodils need consistent moisture post-bloom to support leaf function. Water deeply once a week if rainfall is insufficient, ensuring soil drains well to prevent rot. Apply a low-nitrogen, high-potassium fertilizer (e.g., 5-10-10) after flowering to replenish nutrients. Avoid high-nitrogen formulas, which promote leaf growth over bulb development.
Remove faded flowers (deadheading) to prevent seed production, which diverts energy from the bulb. Use clean shears to snip the flower stem near the base, leaving foliage intact. This practice is especially important in warmer USDA zones (7–9), where daffodils may struggle to store sufficient energy due to shorter post-bloom periods.
Resist braiding or bundling leaves, as this reduces sunlight exposure. If aesthetics are a concern, plant companion perennials (e.g., hostas or daylilies) to camouflage dying foliage. In lawns, delay mowing until leaves yellow. For naturalized daffodils, avoid herbicides that may harm the bulbs.
Every 3–5 years, daffodil clumps may become congested, leading to smaller blooms. Lift bulbs in late spring or early summer once foliage dies back. Gently separate offsets (smaller bulbs) from the parent bulb, discarding any soft or diseased ones. Replant immediately at a depth 2–3 times the bulb's height, spacing them 4–6 inches apart.
Daffodils are generally pest-resistant but may face bulb rot (from soggy soil) or narcissus bulb fly infestations. Ensure well-draining soil and avoid mulch touching the foliage. In areas with bulb flies, cover emerging shoots with lightweight row covers until flowering ends.
In colder zones (3–6), mulch lightly after the ground freezes to protect bulbs from temperature fluctuations. In warmer zones (7–9), bulbs may benefit from partial shade to prevent overheating. Avoid watering during summer dormancy, as excess moisture can cause rot.
Healthy daffodils can thrive for decades with proper care. Avoid planting in areas with heavy summer irrigation. If blooms diminish despite care, test soil pH (ideal: 6.0–7.0) and amend with lime or sulfur as needed. Replenish mulch annually with organic matter to maintain soil structure.
