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Fennel

Florence

Apiaceae

Spacing4 per sq ft
Days to Harvest80d
Expected Yield4 bulbs

Fennel

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Variety History

Florence fennel, named for the Italian city, has been cultivated since the 17th century. It was developed from wild fennel to produce a swollen, bulbous leaf base.

Regional Context

Florence fennel (finocchio) is well-suited to the PNW when grown in spring or fall. Our mild temperatures produce sweet, tender bulbs. Avoid the summer heat window — it will bolt. Two plantings (April and July) give two harvests. Fennel fronds and pollen are bonuses. Bronze fennel (the ornamental variety) also produces excellent fronds and pollen but smaller bulbs.

Growing Technique

Direct sow in April for summer harvest, or July for fall harvest. Fennel bolts in heat — spring and fall are the sweet spots. Sow 1/4" deep, 4 seeds per sq ft. Thin to 8-12" apart. Keep evenly moist; drought stress causes bolting and tough bulbs. When bulbs reach 2-3" at the base, hill soil around them for 2 weeks before harvest to blanch and sweeten. Harvest when bulbs are 3-4" across by cutting at soil level. The feathery fronds are an herb — harvest any time. Allow a few plants to flower for fennel pollen (culinary gold).

Watch For

  • Bolting from heat, drought, or transplant shock — direct sow only, keep consistently moist. Aphids love fennel — spray with water, encourage ladybugs. Bulbs fail to form if crowded — thin ruthlessly. Swallowtail butterfly caterpillars will eat fennel (they love it) — plant extra to share.

Recipes