Among the vast cornucopia of crops grown by the diversified vegetable farmer, there isn’t another quite like the Belgian endive. Also known as witloof – which means “white leaf” in Dutch – Belgian endives are a long season crop that requires a winter, indoor “forcing” phase to produce tightly-wrapped, almond-shaped, cream colored heads. The process has several steps, but in the end is relatively simple and can result in a profitable, delectable harvest of pale, crunchy, nutty, delicately bitter-tasting fresh greens in the winter months.
Growing Belgian endive is a two step process that straddles the seasons. The first step, which begins in the spring, is to cultivate Belgian endive in the field for the roots. The second step, which takes place in the late fall and winter, is to cultivate the heads, called chicons, indoors under moist, dark conditions. This article, the first in a two part series, will address the first step of the process: producing the roots.
But first, some definitions.
What is a Belgian endive anyway?
Belgian endives are in the chicory family, a diverse family of plants with a variety of leaf appearances and head shapes. Curly endive, or frisse, has a lacy, finely cut leaf shape. Broad-leaf, or Batavian endives, have a more gently ruffled leaf shape, resembling a head of lettuce. Radicchio – both red and sugarloaf types – are also in the chicory family. They all have in common a bitter flavor – to varying degrees – and vitamins A, B and C, as well as calcium and potassium.
Historically, endives were cultivated for their roots, which were dried down and used to brew a dark, bitter, coffee-like beverage. In the mid-1800s – so the story goes – a farmer left to go to war, leaving his harvested crop of chicory roots in the cellar. When he returned, he found that the moisture levels in storage were sufficient to cause the roots to sprout, producing tender, edible, mildly bitter, blanched leaves. And so the cultivation of Belgian endive was born.
The Brussels Botanical Garden perfected the forcing process and selected productive varieties. Its export to the US began in 1911. Belgium, the Netherlands and Italy dominated the export of Belgian endive up until the late 1990’s when production was shifted to South America, predominately Chile and Guatemala.
Determining your field planting date:
Belgian endive requires a full growing season for its root development. Depending on the variety, you’ll want to sow it 110 to 140 days before a hard frost. Belgian endive can tolerate light frost, but planting too early in the season can cause bolting. In our 2010 Belgian endive trials here in Northern Vermont, we found that the optimal sowing date was late June/early July.
For optimal root production, Belgian endives prefer direct seeding and culture similar to carrots. They like well-drained, loose soil to promote sufficient development of the roots. Remember, for the first phase of growing endive, the roots are your crop.
The plants prefer a pH of 6.5 or above. Fertility management must be handled carefully as too much nitrogen will promote vigorous top development resulting in poorly formed roots. A side-dressing of phosphorus in the early stages of root development can aide in healthy root formation.
In High Mowing’s 2010 Belgian endive trials, seeds were planted in late June using a hand-push precision seeder with a planting density of 15 seeds/ft in rows 18” apart. Plants were thinned to a 4” plant spacing to allow for uniform sizing when plants averaged 3” tall. In a home garden, seeds can be sown thickly by hand and then thinned to the spacing above.
Physical indications of maturity include reddening of the leaves and desired root size. The optimal root diameter is around 1.5”. Roots that are too small will produce chicons with loose heads; too large and the chicons may have off-shoots. We used a plastic mulch lifter, which has long finger-like forks in the front of the toolbar that use the force of the soil to lift the roots to the surface. Because the soil is lifting the roots up there is minimal breakage of roots and harvesting is more efficient. On a smaller scale, roots can easily be dug with a digging fork, similar to carrots or parsnips. Care should be taken not to nick or damage the roots, since damaged roots may be prone to rotting during storage or forcing.
Allow the roots to dry in the field for a few days or so, covered with straw or with the layered leaves over the roots to prevent exposure to frost and/or direct sunlight. After curing, trim the tops to about 1” above the crown. It is common for growers to trim roots as well, to an 8” length in order to have uniform height in the planting beds. Roots that are forked will still produce chicons, although on a larger production scale they can be more logistically challenging to position in the planting beds.
Belgian endives require a short period of vernalization in order to trigger chicon production. Store endive roots in conditions similar to those favored by other root vegetables – 32-34 degrees with high humidity – for at least a week or until ready for planting. Chicons will emerge about three weeks after replanting the roots. Harvest of the chicons can be staggered by off-setting the replanting of the roots from storage.
Marco Franciosa, a grower in Oregon who specializes in endive production, sings its praises as an important niche crop for his farm and one with significant potential for winter markets, where its freshness is a welcome change amidst the root vegetables. Growing endive is a simple process that requires more patience than anything else. Successful root production is a key component of growing Belgian endives since the roots provide the basis for future growth. What you start with is what you end up with – you won’t get a high quality product from poor quality roots! The result is well worth it: crunchy, succulently fresh winter greens, with a flavor and a texture unlike any other.
Ready to try growing Belgian Endives? You can find organic Belgian Endive seeds on our website.
Stay tuned for our fall article, Belgian Endive Production Part 2: Forcing for Winter Harvest.