Introduction

Shallots, Allium cepa, are closely related to multiplier onions, but smaller, and have unique culinary value. (The term 'multiplier' means that the bulbs multiply freely producing several lateral bulbs). At maturity, shallot bulbs resemble small onions.

Shallots have long been associated with fine French cuisine. They are eaten fresh or cooked, chopped or boiled. Shallots have a delicate onion flavour when cooked that adds to but does not overpower other flavours.

Figure 1. Shallot plant made up of a multitude of small bulbs.

Raw shallots have a strong pungency, stronger than most onions. Their true character comes when lightly sauteed in butter until they are translucent in colour or when used in gravies and creamy sauces. It is very difficult to evaluate shallot quality in the raw form.

Shallots can be successfully produced wherever onions are grown. However, most shallots are produced in Europe, particularly France.

Most shallots consumed in the USA and Canada are imported chopped and dried from Europe. Otherwise, those that are used fresh are consumed green, much like that of green bunching onions, since the mature bulb of the shallot is small.

Taxonomy

The difference between a multiplier onion and shallot is somewhat arbitrary, and they are often lumped together. Commercially however, those with yellow or brown scales and white interiors, such as the 'Dutch Yellow' type, are usually classed as multiplier onions, while those with red scales and, supposedly, a distinctive and more delicate flavour, are classed as shallots.

Taxonomically, there is no such thing as a true shallot.

Many people confuse shallots with green onions, scallions and leeks. The young green onion has a definite bulb formation with the same concentric arrangement that the dry onion has. Scallions are any shoots from the white onion varieties that are pulled before the bulb has formed. Leeks are similar in appearance to scallions but have flat leaves and the white stalk is thicker and longer. The shallot can be distinguished from the others by its distinctive bulbs which are made up of cloves like garlic, but unlike garlic, the individual bulbs are not encircled together by a common membrane. See Figure 1.

Generally, shallot bulbs are the size of chestnuts, sometimes larger, pear-shaped, narrowed in the upper part into a rather longpoint, and covered with a russet coloured skin of a coppery red colour in the lower part shading off into grey towards the upper extremity. See Figure 2.

In the grey shallot, which is sometimes claimed to be the "true shallot", the scales or skin are often wrinkled length-wise and are thick and tough. When the dried skin is taken off, the bulb is often greenish at the base and violet coloured toward the top. The roots are slow drying and persistent. Leaves are small, very green, and 4–5 cm long.

Propagation and Cultural Management

Shallots can be grown from seed, but usually small bulbs are planted in late fall or early spring. The "mother" bulbs divide forming several bulbs.

Although shallots are mostly thought of as dry bulbs, in some areas the green shoots of shallots are used similarly to the green onion or as a scallion substitute.

Plant the bulbs 10–15 cm (4–6") apart. The size of the bulb affects the date of sprouting, plant size and maturity. For uniformity in production, planting similar size bulbs is essential.

For early maturity and harvest, strong, healthy transplants can be used. Transplants can be started 30 to 45 days before direct bulb seeding in the field, and plants can be moved to the field in 30 to 60 days. Don't plant the bulbs or plants deeply and do not move soil to cover the plant base; the bulbs should grow out of the ground for easier dividing.

To harvest over an extended period, plant the largest bulbs (quarter-size) first. After they mature, plant medium-sized bulbs (nickel-size), and finally the smallest bulbs (dime-size). If using transplants, plant one large or two small plants in each hole. Discard the weak clumps and the smallest plants.

To save bulbs for the following year, save only the highest quality bulbs from the highest quality clumps. Many growers market the biggest bulbs and save smaller bulbs for replanting; but this results in gradually smaller and poorer quality shallots. Save bulbs from the biggest and best clumps. These clumps should be as free from disease as possible.

Figure 2. Shallot bulbs cured and ready for market.

Shallots need a continuous supply of nutrients. Split or continuous applications of nitrogen are essential for good growth. Approximately, 75–100 kg/ha of total nitrogen is required for this crop, and its application much like for that of garlic.

The root system is weak and shallow, thus irrigation in the spring and summer is more frequent than for other vegetables. Soil type does not effect the total amount of water needed, but does dictate frequency of water application. Lighter soils need more frequent water applications, but less water applied per application.

Green shallots can be harvested in 30 to 60 days, mature bulbs in 90 to 120 days. Pre-harvest, harvest, and post-harvest management of shallots is similar to that of onions.

Quality and storageability is enhanced by low nitrogen late in the season, proper and adequate field curing, removing tops only after they are dried, and storing the bulbs in a cool, dry area.

One thousand kilograms of seed bulbs should yield 5,000 to 7,000 kilograms of shallots.

Storage

Shallots store well at temperatures of 0–2°C and 60%–70% relative humidity. Because of their small size, shallots tend to pack closely; so they should not be placed into deep piles. Store shallots in slatted crates or trays that allow good air movement in and around the bulbs. This is important to remove excessive moisture and to minimize storage diseases.

Low relative humidity and low temperatures are important to keep shallots sound and dormant and free from sprouting and root growth. At humidities much above 70% and at warmer temperatures of 5–8°C more of the shallots will sprout, develop roots, and decay. With good air flow and humidity control, shallots should store for 8–10 months.

Varieties

Two general types of shallots are available. French-Italian has brownish-red skin, well-shaped bulbs, and a flavour between onion and garlic. Varietal names include Pikant, Atlas, Ambition, Ed’;s Red, and Creation. They can be used either dry or green.

A second type is Welsh shallot. Louisiana Evergreen is one variety. It bulbs poorly, but provides a year-round supply of green shallots for salads, seasonings, or appetizers.

The red shallot is essentially the only one of importance in the market place.

Pests and Diseases

Shallots are susceptible to bacterial diseases, pink root, white rot, downy mildew, purple blotch, onion maggot and thrips. To avoid or minimize these problems, do not plant shallots in the same soil where other Alliums have been grown in recent years, plant only clean, healthy plants or bulbs, and practice good sanitation.

Pest management practices are very similar to onions. The OMAF Factsheet, Onions: Identification of Diseases & Disorders of Onions, Order No. 95-063 and the handbook, Integrated Pest Management for Onions, Carrots, Celery & Lettuce in Ontario provide useful diagnostic, monitoring and management strategies applicable to shallots.