Endive (Cichorium endivia) is a leafy green in the daisy family, closely related to chicory and radicchio, grown for its slightly bitter, nutty-flavored leaves rather than for roots or flowers. The crop comes in two main forms: the finely cut, curly-leaved type known as frisée, and the broader, smoother-leaved type called escarole, which is milder and less bitter. Endive is a cool-season annual that bolts in summer heat, so it performs best in Kentucky as a fall crop or an early-spring one planted well ahead of hot weather. Growing endive is easy once the timing is right, though the plant does benefit from a short period of blanching before harvest to soften its naturally sharp flavor.
Sowing and planting
Endive can be direct-sown or transplanted, and zone 6b gardeners have two realistic windows: an early-spring sowing timed to mature before summer heat arrives, or a late-summer sowing timed to mature in the cooler weeks of fall. Of the two, fall planting is the more forgiving, since the crop heads up as days cool rather than racing a warming spring. For a spring crop, direct-sow or set out transplants in late March to early April, as soon as the soil can be worked; for a fall crop, start seed in mid-to-late July and transplant or direct-sow by mid-August so plants have time to mature before frost.
Sow seed about 1/4 to 1/2 inch (0.5 to 1 cm) deep, and thin or space plants 10 inches (25 cm) apart, with rows 12 to 18 inches (30 to 45 cm) apart. Endive germinates and grows best in cool soil, so a spring sowing started too early in cold, wet ground will simply sit, while one started too late runs straight into bolting weather; err on the early side for spring and the later side for a fall crop timed around the first frost.
Work the bed with compost or aged manure before planting, since endive grows quickly once established and benefits from fertile, well-drained soil. Starting seed indoors three to four weeks ahead of the target transplant date and setting out sturdy young plants, rather than direct-sowing, gives more reliable results for a spring crop in particular, since it shortens the time seedlings spend in unpredictable early-season weather.
Growing on
Keep the soil consistently moist throughout the growing season; endive left to dry out between waterings turns noticeably more bitter and tends to bolt early. A couple inches of mulch helps even out soil moisture and keeps roots cool during warm spells. Feed with a balanced fertilizer at planting and again lightly a few weeks in, since endive is a fast-growing leafy crop that benefits from steady fertility but doesn't need heavy feeding. Weed regularly while plants are small; once the outer leaves spread out, they shade the soil and suppress most competition on their own.
About two to three weeks before harvest, blanch the heads to reduce bitterness: gather the outer leaves up over the center and tie them loosely with twine, or cover each head with an upturned pot or a piece of cardboard, excluding light from the inner leaves for 1 to 2 weeks. Blanch only in dry weather, since trapped moisture in a covered, damp head can encourage rot. Blanch plants in succession rather than all at once if the bed is large, so the whole crop isn't ready to cut on the same day; this also spreads out the risk if a stretch of wet weather moves in partway through the blanching period.
Harvesting
Endive is ready in about 90 days from sowing, though you can begin picking outer leaves earlier if a full blanched head isn't needed. Harvest blanched heads once the covering period is finished, cutting the whole head at the base with a knife. For fall crops, harvest before a hard freeze; light frost doesn't harm the plant and can even mellow its flavor, but a hard freeze damages the leaves.
Unblanched outer leaves can be picked and eaten at any stage if a milder, less work-intensive harvest is preferred. Harvested heads keep for one to two weeks refrigerated, loosely wrapped, and hold their texture better than most lettuces once cut, since the leaves are sturdier and less prone to wilting.
Problems and pests
Leaves taste sharply bitter
Bitterness is usually a response to heat, irregular watering, or an unblanched head rather than a pest or disease. Keep soil consistently moist, harvest before hot weather sets in, and blanch heads for 1 to 2 weeks before cutting to mellow the flavor; escarole varieties are naturally milder than frisée if bitterness remains an issue.
Plant bolts and sends up a flower stalk
Bolting is triggered by a stretch of warm weather, most often in late-planted spring crops or an unusually hot early fall. Once bolted, leaves turn bitter and tough. Prevent it by sowing spring crops early enough to mature before summer heat and timing fall crops to head up as temperatures cool.
Ragged holes chewed through the leaves
Slugs and snails feed on endive's low, close-growing leaves, especially in damp weather, leaving ragged holes and slime trails. Hand-pick at night when they're active, or set out shallow traps of beer sunk to soil level; keeping mulch pulled back slightly from the base of plants reduces the damp hiding spots they favor.
Soft, mushy rot in the center of blanched heads
Rot sets in when moisture gets trapped inside a covered head during blanching, especially in humid or rainy weather. Blanch only when a dry stretch of weather is expected, and check covered heads partway through the blanching period; if rot appears, remove the covering and use the head promptly rather than letting it continue blanching.
Small, sap-sucking insects clustered on new leaves
Aphids gather on young, tender growth, especially in the compact center of the plant, leaving sticky residue behind. A strong jet of water knocks most of them off, and insecticidal soap handles heavier infestations; checking plants regularly catches populations before they build up inside a head that's about to be blanched.
Varieties worth growing
- Galia – A classic frisée type with finely cut, curly leaves and good bolt resistance for a spring planting.
- Tres Fine Maraichere – A traditional French frisée prized for its delicate, deeply frilled leaves and mild flavor once blanched.
- Broad-Leaved Batavian – A standard escarole with wide, smooth leaves and a milder flavor than curly types, reliable for fall crops.
- Natacha – A vigorous escarole with a self-blanching habit that reduces, though doesn't eliminate, the need for tying.
- President – A hardy escarole that tolerates cool fall weather well, suited to a late-season harvest in Kentucky.