How to Grow Florence Fennel Rondo

Florence Fennel Rondo

Foeniculum vulgare var. azoricum

vegetable

Florence Fennel Rondo is a compact, bulbing fennel variety prized for its smooth, white, tender bulbs that develop at the base of the plant. It produces aromatic foliage similar to dill and has a mild, slightly sweet anise flavor. This variety is particularly suited to container growing and shorter growing seasons due to its relatively fast maturation.

Growing Conditions

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Sun: Full sun, 6-8 hours daily; afternoon shade beneficial in hot climates

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Water: Keep soil consistently moist but not waterlogged; provide 1-1.5 inches weekly. Inconsistent watering causes bolting and tough bulbs.

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Spacing: 8-10 inches

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Days to maturity: 70-85 days

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Planting depth: 0.25-0.5 inches; seeds are small and should be surface-sown or barely covered

Soil

Type: Well-draining, fertile loamy soil

pH: 6.0-7.0

Amendments:

Compost aged manure perlite or sand for drainage

Growing Zones

Find your zone →

Thrives in zones 4-9; can be grown in zone 3 with season extension

3a 3b 4a 4b 5a 5b 6a 6b 7a 7b 8a 8b 9a 9b

Growth Stages

Germination & Seedling

2-3 weeks

Seeds sprout in 7-14 days. Seedlings develop fine, feathery foliage resembling dill.

Keep soil consistently moist. Thin seedlings to proper spacing once they have 2-3 true leaves. Protect from strong winds.

Vegetative Growth

3-4 weeks

Plant develops expanded feathery foliage and a small white bulb base begins forming at soil level.

Maintain consistent moisture and provide full sun. Begin earthing up (hilling soil around the base) when bulb reaches golf ball size to blanch and whiten it.

Bulb Development & Blanching

3-4 weeks

Bulb rapidly expands into a white, smooth, multi-layered structure. Regular hilling ensures tender, pale bulbs.

Continue earthing up every 1-2 weeks, covering about half the bulb. Remove any yellowing outer leaves. Maintain consistent watering.

Bulb Maturity & Pre-Harvest

1-2 weeks

Bulb reaches full size (3-4 inches diameter for Rondo), becoming firm and well-blanched. Plant may show signs of slowing growth.

Monitor for bolting tendency. Reduce watering slightly if overly wet. Bulb is ready to harvest when firm to gentle pressure.

Harvest & Storage

Harvest window

Bulb is fully developed, white, tender, and aromatic. Foliage remains green and harvestable.

Cut bulbs at soil level with a sharp knife. Harvest foliage separately for culinary use. Store bulbs in cool conditions (35-40°F) for 1-2 weeks.

Companion Planting

Plan your garden →

Plant with:

Basil Borage Calendula Cilantro Dill Marigold Nasturtium Parsley Thyme Lettuce

Avoid planting near:

Caraway Coriander Dill Kohlrabi Tomato Bean Brassicas (cabbage, broccoli)

Common Pests

Hand-pick caterpillars; allow some damage for butterfly conservation; use row covers on young plants; apply Bacillus thuringiensis if severe.
Spray with strong water stream; introduce ladybugs; use insecticidal soap or neem oil if infestation is heavy.
Increase humidity; spray foliage regularly; use miticide if severe; maintain plant vigor through proper watering.
and
Hand-pick at dawn/dusk; use copper tape barriers; apply diatomaceous earth; set beer traps.
Use row covers until flowering; remove infested plants; plant later to avoid peak egg-laying periods.

Uses

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Fresh & Cooked Fennel Bulb

Culinary

The sweet, tender white bulb can be eaten raw in salads, roasted, braised, grilled, or sautéed. It develops a subtle anise flavor that mellows with cooking. [source]

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Aromatic Foliage & Seeds

Culinary

The feathery fronds add a delicate anise flavor to salads, soups, and fish dishes. The plant also produces flavorful seeds used in cooking and baking. [source]

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Digestive & Nutritional Support

Medicinal

Fennel is traditionally used to support digestive health and may help reduce bloating and gas. Rich in fiber, vitamin C, and potassium. [source]

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Pickling & Preservation

Culinary

Florence fennel bulbs can be pickled whole or sliced, preserving their crisp texture and subtle anise flavor for extended storage. [source]

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Ornamental & Edible Landscaping

Household

The compact Rondo variety's feathery foliage and white bulbs make it attractive in vegetable gardens and containers, serving both aesthetic and culinary purposes. [source]

This is not medical advice. LizPlants is not a medical resource. Always consult a qualified healthcare professional before using plants medicinally.

Harvest Tips

Harvest when bulb is firm and 3-4 inches in diameter, typically 70-85 days after sowing. Cut bulbs at soil level with a sharp knife. Cut foliage separately for use as an herb. Harvest in the morning for best flavor. Young, tender bulbs are more tender and flavorful than large, mature ones. You can also harvest fronds throughout the growing season for fresh use.

Fun Facts

🌱 Florence Fennel 'Rondo' is specifically bred for compact growth and container suitability, making it ideal for small gardens and urban farming.
🌱 Fennel foliage is the larval food plant for the beautiful Black Swallowtail butterfly, making it a wonderful addition to pollinator gardens.
🌱 The name 'fennel' comes from the Latin 'foeniculum,' meaning 'little hay,' referring to the plant's fine, hay-like foliage.

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