When to sow endive

Endive is a crop for the second half of the year. Sow from late May to early August, either straight into the bed or in modules to plant out a few weeks later. June and July sowings give the classic autumn heads; mid- to late-August sowings are for escarole to stand into winter under cover.

Two things make earlier sowings risky. Endive seed needs a soil temperature of at least 59°F and germinates best at 68–72°F, which spring soil rarely offers. And young plants that go through cold spells, with nights around 41°F, are primed to bolt later, even if it warms up again.

If you want an early crop anyway, sow indoors from February or March and keep the seedlings warm until they are planted out in late spring.

Sow about 0.4 in deep, thinly in rows or two or three seeds per module, and keep the seed moist and warm.

Thin or plant out to 12–14 in each way. Endive forms big, flat rosettes and needs the room; crowded plants stay damp and rot more easily. For baby leaves you can sow thickly and cut at about 2 in apart.

A 120 × 80 cm raised bed holds three rows of four at 12 in, 12 heads, or eight if you give them 14 in.

Endive likes sun but tolerates partial shade in summer. Avoid soil that dries out quickly or stays wet.

Water regularly, especially on light soil and in warm weather: drought is one of the triggers for bolting and makes the leaves tough and bitter.

Endive leaves are naturally bitter. Blanching, keeping light off the heart for a while, gives a pale, tender, milder centre. Once a head is full-sized and dry, tie the outer leaves together with soft string, lay a plate or tile over the middle, or put a bucket or pot over the whole plant.

Blanching takes about two weeks, longer in cool autumn weather. Only blanch dry plants and only as many as you will eat soon: covered heads rot quickly in the wet, and slugs love to hide under the covers.

Whether you blanch at all is a matter of taste. Many people enjoy the bitterness, and the outer green leaves are perfectly edible.

Heads are ready about three months after sowing, so June and July sowings are cut from September into late autumn. Cut the whole head just above the soil. Baby leaves for salads can be picked about a month after sowing.

Frisée is best picked before the hard frosts. Escarole is more robust and, under a cloche or fleece, can stand into winter.

Curly endive or frisée (Cichorium endivia var. crispum) has thin, finely cut, frilly leaves. It copes better with summer heat and is the one to grow for late summer and early autumn.

Broad-leaved endive or escarole (var. latifolium), sometimes called Batavian endive, has large, flat, smooth leaves. It is more robust, and the better choice for late autumn and winter harvests.

In US English and on many menus, 'endive' means something else: the pale, tight chicons of witloof or Belgian endive. That is chicory (Cichorium intybus), grown for its roots, which are dug in autumn and forced in the dark. This guide is about garden endive, Cichorium endivia.

Slugs and snails are the main pests, especially in wet autumns and under blanching covers. Aphids can gather in the hearts.

In damp weather, grey mould, leaf spots and bacterial rots attack the heads, above all when they are crowded or kept covered while wet. Spacing and dry blanching are the best prevention.

Bolting comes from cold spells when young, or from heat and drought later on. Sow at the right time and keep the soil evenly moist.

Endive belongs to the daisy family with lettuce, chicory and radicchio, and shares soil-borne diseases with them. Don't grow it where lettuce or chicory grew the year before; a three-to-four-year break for the whole group is the safe choice.

Because it is sown in summer, endive is an ideal follow-on crop: it goes into beds cleared of early potatoes, peas, early carrots or spring onions. That is the most useful 'companion' advice there is.

Planting tables also pair endive with fennel, leeks or beans. We found no solid evidence for these pairings; treat them as tradition.