Browse all plants

annual vegetable

American Flag leek

American Flag leek is an annual vegetable noted for cold-hardy leek and long blanched shafts. It grows in USDA zones 3a-9a, prefers full sun, part sun and loam and clay soils, and harvest timing is stalks in fall and winter.

Search Amazon
cold-hardy leeklong blanched shafts

Fit and caveats

American Flag leek is an allium crop where day length, planting season, and curing matter. The right choice depends on whether the gardener wants bulbs, greens, cloves, or a perennial clump.

Best fit

  • Beds in its listed growing range with full sun, loose soil, and low weed pressure.
  • Gardeners who match onion type to day length and local planting windows.
  • Sites where weeds can be controlled because alliums compete poorly.

Use caution

  • Onions are day-length sensitive; the wrong type can make leaves without good bulbs.
  • Alliums are shallow-rooted and do not handle weed competition well.
  • Overwatering near maturity can reduce storage quality.
  • Cure storage bulbs in dry airflow before long storage.

Regional notes

  • In Southern ZIPs, short-day onions and fall/winter planting windows often matter.
  • In northern ZIPs, long-day onions and fall-planted hardneck garlic are often better fits.
  • Perennial alliums can be useful in small gardens, but clumps still need dividing and containment.

Comparison note: Compared with carrots or beets, American Flag leek is less about root shape and more about day length, planting timing, and curing. Compare alliums by harvest goal: green tops, bulbs, cloves, or perennial divisions.

Photos

Leek plant showing upright blue-green leaves and thick edible stems.
Plant photo Leek plant showing upright blue-green leaves and thick edible stems.

Photos show a representative plant in the garden. Fruit color, size, and growth habit can vary by cultivar, season, nursery stock, and site.

Photo sources: Schlaghecken Josef / Wikimedia Commons (CC BY-SA 4.0)

Harvest and uses

Harvest window
stalks in fall and winter
Yield return
0.3-0.8 lb/plant/season
First harvest
90-120 days
Best for
Vegetables & herbs
Notable traits
cold-hardy leek, long blanched shafts
Supplier search: Amazon Search Amazon

Spacing, yield, and timing

How far apart should you plant American Flag leek?

Plant American Flag leek at 0.3-0.5 ft in-row x 1-1.5 ft rows. Adjust this starting point for trellises, hedges, rootstock, containers, pruning style, or local extension guidance.

How much does American Flag leek produce?

American Flag leek yield is modeled as 0.3-0.8 lb/plant/season. Treat that as a planning range, because weather, soil, watering, pruning, pests, and local pressure can change the real result.

How long does American Flag leek take to produce?

American Flag leek usually reaches first useful harvest or display in 90-120 days under suitable conditions.

How do you grow American Flag leek?

Grow American Flag leek in USDA zones 3a-9a with full, partial light, loam, clay soil, and medium water. Use 0.3-0.5 ft in-row x 1-1.5 ft rows for layout planning. Match the plant to drainage, heat, chill, and pest pressure before scaling up.

Can American Flag leek grow in a container?

American Flag leek can start with a container of about 5+ gal (workable). Larger containers usually buffer heat and moisture swings better than the minimum.

10-year return
3-8 lb/10 yrs
Full output
This season
Planting depth
Plant 0.5-1 in deep
Productive life
1 yrs
Difficulty
2/5
Reliability
4/5
Data quality
Low profile, Low yield confidence

Yield varies most with climate, soil, rootstock, pruning, pest pressure, and wildlife.

Estimated Pound Return

Low yield confidence
0 lb 0.3 lb 0.5 lb 0.8 lb 1 lb Source range Expected midpoint Y1 Y2 Y3 Y4 Y5 Y6 Y7 Y8 Y9 Y10
Year 1
0.3-0.8 lb
First-year estimate from the sourced curve.
Year 5
0.3-0.8 lb
Year 10
0.3-0.8 lb
10-year total
3-8 lb/10 yrs

Shaded band shows the sourced low-to-high pound-yield range. The line tracks the midpoint for quick comparison.

Method: direct pound yield from crop metric source. Annual crops assume one comparable planting per year; perennial crops ramp from first bearing to full production.

Planting, care, and risk checks

Checklist

8 items

Affiliate links may earn a commission.

  • Seed-starting trays

    Propagation / Pre-season

    Start annual vegetables, herbs, and flowers ahead of transplant season.

    View
  • Right-size container with drainage

    Containers / Before planting

    Use a container large enough for mature roots, with open drainage holes to prevent root rot.

    View
  • Expanding container potting mix

    Containers / Before planting

    Use a lighter container medium instead of dense garden soil in pots and grow bags.

    View
  • Seedling grow light

    Propagation / Pre-season

    Keep indoor seedlings compact and sturdy before they move outside.

    View
  • Floating row cover

    Protection / At planting

    Protect young crops from wind, light frost, and early pest pressure while still letting light and water through.

    View
  • Balanced garden fertilizer

    Nutrition / During growth

    Feed annual vegetables, herbs, flowers, and hungry container crops according to soil or label guidance.

    View
  • Soil thermometer

    Timing / Before planting

    Check whether spring soil is actually warm enough for direct sowing, transplanting, and tender warm-season crops.

    View
  • Soil test kit or lab mailer

    Site prep / Before planting

    Check pH and baseline nutrients before adding amendments, especially for fruiting crops, native beds, and acid-loving plants.

    View

Planting strategy

  • Planting depth: Plant 0.5-1 in deep
  • Container minimum: 5+ gal (workable). Use 5+ gal for most single vegetable plants; smaller leafy/root crops can use less.
  • Start with one plant when testing fit in a new bed or container.
  • Plant more than one when harvest volume or pollination is the main goal.

Risk factors

  • Deer pressure: Not rated. No deer-resistance category is assigned yet; treat browsing risk as local and variable.
  • Black walnut: Mixed or uncertain. Use as a black walnut / juglone planning cue; tolerance varies by cultivar, soil, and distance from the tree.
  • Match the site first: full, partial light, loam, clay soil, and medium water.
  • Use 0.3-0.5 ft in-row x 1-1.5 ft rows as the first spacing model; adjust for hedges, trellises, containers, or local guidance.
  • Plan around mature size: 1-2 ft H x 0.3-0.5 ft W.
  • For harvest planning, treat "stalks in fall and winter" and 0.3-0.8 lb/plant/season as planning ranges, not guarantees.
  • Quantitative data quality is low for this record; verify before buying or planting at scale.

Comparable plants

Sources and methodology

This guide combines hardiness range, light, soil, water, harvest timing, traits, supplier links, plant relationships, and quantitative planning metrics. Pairings are screened for practical garden fit.

Quantitative values use extension and botanical-reference ranges where available. For less-studied cultivars, similar crops fill gaps conservatively. Ranges are intentionally broad so the profile stays useful without pretending to be exact.

Supplier search: Amazon. Search links are not paid placements unless explicitly marked; affiliate listings may earn a commission. Last reviewed: 2026-05-31.