How to cultivate the sweet, bulbous magic of Florence fennel
Often confused with its feathery herb cousins, Florence fennel is a prize for the no-dig gardener. With a sweet aniseed flavour and the potential to reach impressive weights, this umbellifer offers a rewarding harvest if you master the art of minimal soil disturbance.
Florence fennel, or bulb fennel, belongs to the umbellifer family alongside carrots and parsnips. Unlike long-stemmed fennel varieties grown primarily as herbs, this cultivar is prized for its tender, swelling bulbs. When grown successfully, these bulbs can fatten to over 450g, offering a refreshing aniseed flavour in salads or a creamy sweetness when cooked in soups and ratatouille.
The no-dig method provides an ideal environment for this perennial. Rather than traditional digging, which can destroy fungal networks and drainage channels created by worms, no-dig gardening relies on adding thick layers of organic matter. For new beds, laying overlapping sheets of plain cardboard—free of staples or shiny print—and weighting them with 10-1im of mulch helps suppress weeds and preserve soil structure. This approach avoids releasing locked carbon and maintains the natural nutrient-access pathways for plants.
To achieve large bulbs, spacing is critical. Planting one bulb per station, approximately 22 centimetres apart, ensures maximum growth, whereas tighter spacing may result in smaller yields. For those starting from seed, sowing into module trays using a mix of about 60% homemade compost and 20% proprietary compost is effective. As the plant matures, watch for the bulbs to begin swelling on the surface after roughly six weeks. If the plant begins to bolt, indicated by elongating bulbs, it is best to harvest and eat them immediately to enjoy their rich flavour.
Source: Grow Early Fennel 🌱 From Sowing to Harvest | No Dig Gardening
