Allium cepa (Aggregatum Group)
Last revised February 15, 2010
VARIETIES AND PLANTING STOCK
Shallots are normally propagated from bulb divisions. In addition, true seed of shallots is now available in both red and yellow types.
Shallots propagated from bulb divisions:
French Red Shallot - red type is the most common dry shallot grown. Other yellow or white varieties include Griselle, Chicken Leg Shallot, and Dutch Yellow, but only the red shallot is important in the market.
PLANTING
Shallot bulbs may be planted in spring or fall in Oregon. Fall planting eliminates the need for storing planting stock, but requires maintenance of the planting through the winter and increases the risk of undesirable seed stalk formation. Fall plantings would be slightly earlier in maturity. Spring plantings may be made anytime the soil can be made ready for planting up to the middle of June in most locations.
Fall plant around September 15 for a mid-June harvest. Spring plant around March 15 for a mid-July harvest.
Shallots respond --as do all varieties of Allium cepa-- to daylength. Bulbing is initiated with lengthening days. When fall-planted, shallots do not immediately initiate bulbing since the days are becoming shorter. If you plant small bulbs of shallots or multiplier onion (which would have few meristematic growing points), you tend to get larger bulbs in the subsequent crop. Conversely, if you plant larger bulbs, which will have more growing points, you get more but smaller bulbs. Adjust your planting sizes to meet your market specifications.
All else being equal, when you plant shallots and multiplier onions where daylengths are rapidly increasing (as in extreme northern latitudes), bulbing begins before the plants have had time to develop the normal number of leaf initials, so the bulbs produced will be smaller than normal.
If you plant shallots in the fall and experience a long, mild winter, you may have a long period in which growth starts and stops, resulting in many growing points and smaller bulbs than if the shallots were planted in spring when growth would tend to be more continuous and uniform. Shallots produced from true seed also behave as just described for shallots produced from bulbs.
There are many differences between shallot varieties in daylength requirements. There are also interactions with temperature and plant size, but all shallots, as well as all other Allium cepa varieties, bulb with lengthening days and are thus categorized as photoperiod responsive.
Plant 3-4 bulbs per foot and space rows 18-24 inches apart. Plant the sets 1 inch deep and root plate down if possible. However, adequate yields can be obtained from randomly dropping the planting stock. Use 200-300 lb of planting stock per acre. Choose only clean, disease-free bulbs for planting stock.
Garlic planters may be used with shallots. Planting equipment for garlic is specialized and often custom built. A Canadian company that manufactures a planter suitable for garlic and shallots is BDK Fabrication, 240 Argyle St., Delhi, Ontario, N4B 2W8. The contact person is Mr. Don Haskins, 519-582-8348. BDK Fabrication also manufactures single and multiple-row harvesters. For small acreage plantings, a potato attachment designed to be used with a Holland Transplanter may be suitable for use. Contact the Holland Transplanter Co., 510 East 16th St., Holland, MI 49423-0535. Another machine is the Model 4000 carousel plug transplanter from Mechanical Transplanter Co., 1150 S. Central Ave., Holland, MI 49423. Cloves must be individually hand-fed in the latter machine.
SOIL
Sandy loam or loam soils are preferred, but shallots have been successfully produced on a wide range of soils.
FERTILIZER
For the most current advice, see Nutrient Management for Sustainable Vegetable Cropping Systems in Western Oregon, available as a free download from the OSU Extension Catalog
The following are general recommendations. It is advisable to use a soil test for each field to be planted.
Nitrogen: 50 lb N/acre applied at planting time for fall planted fields. Apply an additional 60-90 lb N/acre in spring, or use that amount for spring planted fields.
Fertilizer materials such as AN-20, ammonium thiosulfate, and monocarbamide dihydrogensulfate can be used to provide ancillary weed control in Alliums, including shallots. See the file Nitrogen Fertilizer Solutions Providing Ancillary Weed Control in Alliums.
Phosphorus: 75-100 (P2O5) lb/acre. All P should be banded and applied at planting.
Potassium: 50-100 (K2O) lb/acre
Sulfur: 50 (S) lb/acre
IRRIGATION
Apply water uniformly. Shallots are shallow rooted and benefit from frequent irrigation. Reduce irrigation as bulbs reach marketable size to reduce disease problems and facilitate curing.
Soil type does not affect the amount of total water needed, but does dictate frequency of water application. Lighter soils need more frequent water applications, but less water applied per application.
HARVESTING, HANDLING, AND STORAGE
Shallots may yield approximately 9-12 tons per acre. Harvest shallots when bulbs are fully mature, well colored, and 1-2 inches in diameter. Allow to cure in sacks, or bins, or under cover. Although shallots can be harvested several ways, single or multiple-row harvesters can be custom built by Krier Engineering, 4774 Morrow Rd., Modesto, CA. Contact Mr. Alex Krier, 800-344-3218, for more information.
Shallots are usually hand cleaned, topped and put into bags or bins for storage after the necks and bulbs are well cured.
Shallots store well at temperatures of 32-35 F and 60-70% relative humidity. Because of their small size, shallots tend to pack closely; so they should not be place into deep piles. Store shallots on 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 temperature are important to keep shallots sound and dormant and free from sprouting and root growth. At humidities above 70% and warmer temperatures (40 to 50 F) shallots will sprout, develop roots, and decay more rapidly. With good air flow and humidity control, shallots should store for 8 to 10 months.
SPROUTING INHIBITION
Apply maleic hydrazide (Royal MH-30) at 2 lb aia when bulbs are fully mature with soft necks and 5 to 8 green leaves, or when approximately 50% of the tops have fallen, but are still green. Should be applied at temperatures below 80 to 85 F to avoid crystallization on leaf surfaces. Use of a spray adjuvant is suggested in arid regions west of the Rocky Mountains. Avoid early sprays before maturity to reduce sponginess. Do not treat seed shallots.
PACKAGING
Dry shallots are shipped to wholesale distributors in 50-lb sacks, in film bags or quart containers holding 1 to 1.5 lb or in 5-lb mesh bags. Consumer packaging is done in small mesh bags, windowed boxes or trays holding 5-7 bulbs each.