Froots & Veg

Roots & tubers

Florence fennel

For roasting; best as a fall crop.

Outside
Direct mid Jul, fall crop only
Where
Raised bed or in ground
Sun
Full sun
Water
Even, never dry; any drought invites bolting
Harvest
Oct, before hard freeze

Care

Water
Even, consistent moisture with no dry spell, because drought is the surest trigger for bolting in a first-year plant. A deep soak once or twice a week, every 3 to 4 days in a September warm spell, the finger test deciding, keeps the bulb swelling steadily.
Sow
Sow direct in mid July only, a quarter inch deep, in rows 18 inches apart, and never transplant it, since a disturbed root bolts. Thin to about 10 inches so the bulbs have room to fatten. Sowing after the solstice earns the bulb, cueing the plant to swell rather than run to seed.
Feed
Fennel likes fertility: a shovel of compost or castings worked in at sowing, then a monthly top-dress of slow-release organic fertilizer across the short fall run. Keep it steady rather than heavy, since a nitrogen surge favors leaf and stalk over a tight, heavy bulb.
Ready
Harvest through October, before a hard freeze, once the base has swelled fist-sized and firm. Cut across the root plate at soil level rather than pulling. Take it before the bulb elongates or splits and turns coarse.
Trouble
A flower stalk instead of a bulb: heat, long days, or drought stress, which is exactly why it goes in only after midsummer and never runs dry. A loose, elongating base: left too long, so cut at the first sign the bulb stops tightening.

In a bag?

Yes
Up to a 5–7 gal bag.
Water
Daily in warm spells; bags dry far faster than a bed, and a fennel that dries out bolts instead of bulbing. 30 to 40 sec on the shower dial until it runs from the seams.
Feed
Top-dress monthly; every watering leaches the bag.
Sow
One or two plants per bag, thinned from a direct sowing.

Florence fennel makes fat roasting bulbs here only as a fall crop, sown in July for an October harvest. Spring sowings answer the lengthening days by bolting, so they are not offered the chance.

Growing

Direct sow in mid July, thin to ten inches, and treat it gently: even moisture, no crowding, no transplant shock, because every stress reads as an invitation to bolt. As bulbs swell in September, pull a little soil against them to keep the bases white. Cut at the root plate through October before hard freeze; the after-the-solstice timing does the real work, telling the plant to bulb instead of flower.

Varieties

Zefa Fino was selected for bolt resistance and is the right seed for the job; Perfection is the traditional runner-up.

In the kitchen

Roasted wedges go caramel at the edges and quietly sweet, nothing like the raw anise snap. Shaved raw with lemon it sharpens a fall salad, and the fronds are a free herb.

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