In late August, once the summer lettuce has bolted and you've pulled it out, the row sits empty — the same stretch you'd been picking outer leaves from all season. A lot of gardeners fill it with chicory (Cichorium intybus). In the Northern Hemisphere the sowing windows are March–April and August–September, and seed sown in late summer keeps making leaves into October and November. Then the first harvest arrives, you pick a leaf, put it in your mouth, and type more or less the same thing into a search bar. Why is it this bitter?
What Makes It Bitter
Chicory's bitterness comes from lactucopicrin and lactucin. Both belong to the sesquiterpene lactones — the same family of compounds as the milky sap that beads up when you cut a lettuce stem. Chicory sits in the genus Cichorium and lettuce in Lactuca, both within the daisy family; different genera, and yet the compounds behind the bitterness overlap.
There isn't enough evidence to say what those compounds do in the body. When the leaves are eaten as a vegetable, what's been established in humans stops at the composition itself. So treat the bitterness as a matter of flavor. And a matter of flavor can be handled in the bed.
How Bitter It Gets Is Decided Ten Days Before Harvest
Forty days after sowing, you can begin taking the outer leaves. Strip them off in rounds instead of pulling the whole plant and a single crown will feed you several times over. To soften the flavor, put the last ten days to work. Block the light ten days before harvest and the bitterness drops noticeably. Invert a flowerpot over the plant or set a black crate on top, and gather the outer leaves into a loose tie so no light reaches the heart. Keep watering as usual, but lift the cover once a day so it doesn't go damp underneath.
Starved of light, the inner leaves pale and turn mild. Belgium, France, the Netherlands, Poland, and Italy grow the most chicory, and this business of shutting out the light to force a tender heart is their method.
Where the Names Get Tangled
The Donguibogam, the great Korean medical compendium, carries an entry for gogeo (苦苣) in its vegetables section, describing it as cold in nature and bitter in taste. A gloss adds that gogeo is the same as yageo (野苣), also called pyeongeo (褊苣), and the root is listed separately. It stands apart from wageo (萵苣), lettuce, in that same section. Which plant gogeo actually names today is disputed: some read it into the chicory group, while Korean herbal tradition reads it as ssambagwi (Ixeris species), a different bitter green altogether. It is a record from an old medical text, and it doesn't line up with how we'd sort things now.
The English names blur too. The plants sold as wild lettuce (Lactuca virosa, Lactuca serriola) belong to Lactuca alongside garden lettuce, which puts them in a different genus from chicory entirely. This is what happens when bitter greens end up sharing names, so it's worth checking the botanical name on the seed packet. To line up sowing months and harvest months in one place, open the chicory entry in the Homiclub crop guide and copy the dates onto your calendar.
Taming the Bitterness at the Table
Fat softens bitterness. When you tear the leaves into a salad, be generous with the olive oil and scatter crushed walnuts or pine nuts over the top. Radicchio, with its red-streaked leaves, takes well to a brush of oil and a turn in a hot pan.
Alongside grilled meat, use chicory instead of lettuce for ssam — the Korean way of wrapping a bite of meat in a leaf. The leaves are thin without being tough, so one alone is enough to hold a wrap, and the bitterness cuts the richness of pork belly. If that's more bite than you want, fill the plate half with chicory and half with lettuce.
Roots dug in fall have a use of their own. Wash them, slice them thin, dry them, then roast them dark and they give off something close to the smell of coffee. Caffeine-free, they get brewed in place of coffee or blended into the ground beans. The practice spread through Europe when Napoleon's Continental Blockade cut off the coffee supply, and it survives in the coffee of New Orleans. The roots run 15–20% inulin by fresh weight, which also makes them a raw material for extracting the polysaccharide that ferments in the gut.
Where It Meets the Body
- Chicory is in the daisy family, so anyone with a mugwort or ragweed pollen allergy may get a cross-reaction. The first time you eat it, stop and take stock if your mouth itches or your throat feels tight. Contact dermatitis caused by the sesquiterpene lactones has been reported as well.
- Inulin is fermented by bacteria in the large intestine, and that fermentation makes gas. Jumping straight to 10 g or more a day of root powder or a supplement tends to bring bloating and loose stools. When you raise the amount, start small and build up over several days. Eating the leaves as a cooked green won't get you anywhere near that.
- There are reports that chicory root increases bile flow. If you have gallstones or have ever had a blocked bile duct, skip the root concentrates and extracts, and see a doctor before using them. Eating the leaves and taking a root concentrate are two different things.
If you sowed in late summer, put two dates on the calendar. Forty days from the sowing date is your first harvest; ten days before that is the day the cover goes on. Keep the earlier date and the leaves you pick on the later one will taste different.
