American Flag Leek is a member of the onion family and has thick, fleshy, white 8-10-inch tall stalks that are about 1 inch at the base. Unlike green onions, leeks do not form a bulb and have very wide leaves. These stems are tender and have excellent flavor, making them ideal fresh or cooked in soups. American Flag Leeks offer versatility in the kitchen, adding depth and flavor to soups, stews, and sautes, while also serving as a delightful substitute for onions in many recipes. Its rich, buttery flavor is a gourmet's dream, elevating even the simplest dishes. This leek grows well in smaller spaces, making it ideal for home gardeners with limited room. Its frost resistance means it can be harvested late into the season, providing fresh produce when other crops are gone. Leeks can be bunched and harvested early when they are about the size of a finger or pencil, or they can be thinned and allowed to grow to a much larger mature size. Also Known As: American Flag Leek, Flag Leek, Ornamental Leek, Wild Leek, Spring Onion, Leek Onion, Garden Leek, Allium Ampeloprasum, Scallion, Elephant Leek. Plant Name: Leek, American Flag Latin Name: Allium ampeloprasum Days to Germinate: 7-14 Days to Harvest: 120 Plant Height: 12 - 18 Inches Spread: 6 - 8 Inches Growth Habit: Root USDA Zones: 3-9 Lifespan: Perennial Brand: TomorrowSeeds Sunlight: Full Sun, Partial Shade Pollination: Heirloom, Open-Pollinated GMO: No Fungicide-Treated Seeds*: No Seeds Packed For**: 2026 *Fungicide-treated seeds protect the seedlings from diseases until they are up and growing. Do not eat treated seeds. **Seeds are freshly packed for the growing season of the year listed. Seeds are still viable beyond pack date. Store in a cool and dry location such as the refrigerator or basement to best preserve germination rates. Planting Instructions: Soil Preparation: Choose an area with heavy, well-draining soil that receives at least 6 hours of sunlight each day. Remove weeds, large rocks, and litter from the planting area. Leave small weeds and dead grass, they will enrich the soil when turned under. Spade or till the soil 8-12 inches deep. Loosening the soil will help the plant establish strong roots. Plants grow best in soil with lots of organic matter. You may optionally add fertilizer or organic material such as compost, leaves, or rotted hay to mix into the soil at this point. For small gardens, scatter 2-3 tablespoons of fertilizer evenly and work into the top 2-3 inches of soil for each hill or 2 foot by 2 foot planting area. For larger gardens, scatter 2-3 pounds of a complete fertilizer for each 100 square feet of planting area. Work fertilizer or organic material into the soil and leave the surface smooth. Form rows of soil beds 4-6 inches high and at least 12 inches apart. This formation of ridges will help with drainage. Planting: Leeks grows best in cool weather, thriving in 60F-70F soil temperatures. Plant Leeks in the spring as soon as the soil can be worked, about 2-4 weeks before the last frost in spring. Optionally, start Leeks indoors 8-10 weeks before the last frost in Spring. Harden off, then divide clumps 6 inches apart outdoors when the soil reaches 55F. For fall crops, direct sow seeds outdoors 2-4 weeks before the first frost. Established Leeks can be mulched and overwintered. To plant, make holes 1/4 inch deep and spaced 6 inches apart down the rows of raised beds. Plant 5 seeds per hole. Cover seeds thinly with soil and water after planting. Or, broadcast seeds and separate clumps to the desired spacing when seedlings come up. If you want a continuous supply throughout the fall, you can sow seeds every 2-3 weeks. Planting Depth: 1/4 inch Within-Row Spacing: 6 inches Between-Row Spacing: 12-18 inches Care During the Season: Watering: Water the plants, soaking the soil to a depth of 6-8 inches, once a week. If there is no rainfall, water 2 times a week. Sandy soils may need to be watered more often than heavy clay soils. Weeding: Keeping plants weed-free improves production. If plowing or hoeing, do not dig to deeply to prevent from cutting the feeder roots. Fertilizing: Once leeks are as thick as a pencil, you may optionally apply a light or diluted dressing of a complete fertilizer once a month during the growing season, without letting the fertilizer touch the plants. Water plants after fertilizing. Insecticides: Insecticides may be used to protect plants. Bt-based insecticides and sulfur are organic options that can be used for prevention. Sulfur also has fungicidal properties and helps in controlling many diseases. Before using a pesticide, read the label and follow cautions, warnings and directions. Diseases: If spots or mold appear, treat plants with an approved fungicide. Neem oil, sulfur, and other fungicides may be used. When using fungicides always follow label directions. Harvesting: American Flag Leek can be harvested when the bulbs are about 1 to 2 inches in diameter, about 90 to 120 days after planting. To check if they’re ready, gently pull up one or two leeks to assess their size. The best time to harvest is in the late summer to early fall, before the first frost hits, as leeks can tolerate light frosts but are best harvested before severe cold. You can pull the leeks up carefully by hand or use a spade to loosen the soil around them. Once harvested, trim the roots and tops, and store them in a cool, dry place. Harvest the largest plants first so that those left can continue to grow. You may also cut leeks at the base, leaving an inch above the ground. Leeks will continue to grow at the cut point.
