Heirloom

Scallion, Evergreen Hardy White

Allium fistulosum

Wikimedia Commons

Green thread-like leaves. Adds delicate pungency where a mild onion flavor is needed.

Harvest

16-25d

Days to harvest

📅

Sun

Full sun to partial shade

☀️

Zones

4–9

USDA hardiness

🗺️

Height

1-3 feet

📏

Planting Timeline

Zone:

Jan

Feb

Mar

Apr

May

Jun

Jul

Aug

Sep

Oct

Nov

Dec

Start Indoors

Harvest

Start Indoors

Harvest

Showing dates for Scallion, Evergreen Hardy White in USDA Zone 7

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Zone Map

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Scallion, Evergreen Hardy White · Zones 4–9

What grows well in Zone 7? →

Growing Details

Difficulty

Easy

SpacingNot applicable for microgreens (dense sowing)

SoilSeed-starting mix, potting mix, or coconut coir

WaterConsistent moisture; keep substrate damp but not waterlogged

SeasonWarm season annual

FlavorMild, delicate onion flavor with subtle pungency—refined and sophisticated without sharp bite, fresh and slightly sweet

ColorBright green

Zone-by-Zone Planting Calendar

Zone	Indoor Start	Transplant	Direct Sow	Harvest
Zone 1	January – December	—	—	January – December
Zone 2	January – December	—	—	January – December
Zone 11	January – December	—	—	January – December
Zone 12	January – December	—	—	January – December
Zone 13	January – December	—	—	January – December
Zone 3	January – December	—	—	January – December
Zone 4	January – December	—	—	January – December
Zone 5	January – December	—	—	January – December
Zone 6	January – December	—	—	January – December
Zone 7	January – December	—	—	January – December
Zone 8	January – December	—	—	January – December
Zone 9	January – December	—	—	January – December
Zone 10	January – December	—	—	January – December

Succession Planting

Because Evergreen Hardy White scallion microgreens are ready to cut in 16–25 days and don't regrow meaningfully after a single harvest, succession sowing is how you keep a steady supply going. Start a new tray every 7–10 days and you'll always have one in early germination, one mid-growth, and one ready to cut. That three-tray rotation works year-round indoors — Allium fistulosum needs no cold stratification and no outdoor bed.

If you're growing on a windowsill through the shorter days of December and January, expect the slower end of that range — closer to 25 days. Under a grow light on a 16-hour cycle, you can reliably hit 16–18 days. Factor that difference into your sow schedule so you're not caught with a gap between trays.

Complete Growing Guide

Green thread-like leaves. Adds delicate pungency where a mild onion flavor is needed. According to Johnny's Selected Seeds, Scallion, Evergreen Hardy White is 16 - 25 days to maturity, annual, open pollinated. Notable features: Hydroponic Performer.

Light: Full sun (6 or more hours of direct sunlight a day), Partial Shade (Direct sunlight only part of the day, 2-6 hours). Soil: High Organic Matter, Loam (Silt), Sand. Drainage: Good Drainage. Height: 1 ft. 0 in. - 3 ft. 0 in.. Spread: 0 ft. 6 in. - 2 ft. 0 in.. Spacing: Less than 12 inches. Growth rate: Medium. Maintenance: Low. Propagation: Division. Regions: Coastal, Mountains, Piedmont.

Harvesting

Scallion, Evergreen Hardy White reaches harvest at 16 - 25 days from sowing per Johnny's Selected Seeds. As an annual, harvest continues until frost ends the season.

The capsule splits longitudinally and contains small round black seeds.

Type: Capsule.

Storage & Preservation

Harvest Evergreen Hardy White scallion microgreens at 16 days and store immediately in a breathable container lined with paper towels at 32–40°F with 90–95% humidity. A perforated plastic clamshell or open bag in the refrigerator works well. Expect 7–10 days of usable freshness before wilting becomes pronounced. For longer storage, freeze whole microgreens on a tray before transferring to freezer bags; they'll keep three months but lose crispness, making them best suited for cooked dishes, soups, and garnishes. Drying is also effective—spread on a screen in a warm, airy location for 5–7 days until completely brittle, then store in airtight containers for several months. Because this variety tolerates cool conditions better than most alliums, slightly lower refrigeration temperatures (closer to 32°F) extend shelf life without damage. Avoid moisture accumulation to prevent mold and slime.

History & Origin

Scallion, Evergreen Hardy White is open-pollinated, meaning seed saved from healthy plants will produce true-to-type offspring. Listed in the Johnny's Selected Seeds catalog.

Origin: Northern Hemisphere, North America and Eurasia

Advantages

+Delicate mild onion flavor enhances dishes without overpowering other ingredients
+Quick 16-25 day harvest fits fast production schedules efficiently
+Easy difficulty level makes it ideal for beginner microgreen growers
+Thread-like leaves add elegant visual presentation to finished plates
+Hardy variety tolerates temperature fluctuations better than delicate microgreens

Considerations

-Thin leaves prone to clumping when wet, requiring careful misting technique
-Lower yield per tray compared to heartier microgreen varieties
-Allium species susceptible to fusarium and root rot in humid conditions
-Requires consistent airflow to prevent fungal issues during growth phase

Companion Plants

Scallion microgreens grow in trays, not beds, so traditional in-ground companion planting doesn't apply directly — but if you're running multiple microgreen trays at once, basil and lettuce are good ones to grow alongside. They share similar moisture needs and tolerate the same 4–6 hour light window, so one watering routine and one light position covers all three without anyone getting shortchanged. In our zone 7 Georgia garden, where summers push humidity indoors as well as out, keeping a potted marigold near your growing station genuinely cuts down on fungus gnat pressure across the whole setup.

Beans and peas are worth keeping well away from your Allium fistulosum trays. Alliums release compounds that suppress the nitrogen-fixing rhizobia bacteria legumes depend on — it's a documented allelopathic effect, not gardening folklore. In adjacent trays sharing a drip tray or drain mat, that root-zone chemistry can still transfer. Sow your legume microgreens on a separate shelf or station entirely.

Plant Together

Basil

Repels aphids and thrips that commonly attack scallions, enhances growth

Carrots

Scallions repel carrot flies while carrots help break up soil for shallow scallion roots

Tomatoes

Scallions deter aphids and spider mites from tomatoes, improve tomato flavor

Lettuce

Similar water and nutrient needs, scallions provide natural pest deterrent for lettuce

Cabbage

Scallions repel cabbage worms and flea beetles that damage brassicas

Spinach

Compatible growth habits and nutrient requirements, mutual pest protection

Marigolds

Attract beneficial insects and repel nematodes that can damage scallion roots

Parsley

Similar growing conditions, both herbs complement each other's pest-repelling properties

Keep Apart

Beans

Nitrogen fixation can cause excessive leaf growth in scallions at expense of bulb development

Peas

Heavy nitrogen production leads to weak, overly leafy scallion growth

Sage

Strong allelopathic compounds can inhibit scallion germination and growth

Nutrition Facts

Calories

32kcal(2%)

Protein

1.83g(4%)

Fiber

2.6g(9%)

Carbs

7.34g(3%)

Fat

0.19g(0%)

Vitamin C

18.8mg(21%)

Vitamin A

50mcg(6%)

Vitamin K

207mcg(173%)

Iron

1.48mg(8%)

Calcium

72mg(6%)

Potassium

276mg(6%)

Per 100g serving. % Daily Value based on 2,000 calorie diet. Source: USDA FoodData Central (FDC #170005)

Pests & Disease Resistance

Common Pests

Fungus gnats, spider mites (rare in microgreens); primarily a concern only if debris or old substrate is present

Diseases

Damping off (prevented by proper ventilation and moisture control), mold (prevented by air circulation and avoiding overwatering)

Troubleshooting Scallion, Evergreen Hardy White

What you'll see, why it happens, and what to do about it.

Pale, leggy seedlings flopping over by day 10–12, stems thin as thread

Likely Causes

Insufficient light — microgreens need 4–6 hours minimum, and a weak grow light placed too far above the tray is a common setup mistake
Sown too densely without enough airflow, causing stems to stretch toward any available light

What to Do

1.Move trays to your brightest south-facing window or drop a grow light to within 2–3 inches of the canopy
2.Next sow, back off seed density slightly — Evergreen Hardy White is a big seed for a microgreen; shoulder-to-shoulder coverage is fine but you don't need to pile them
3.A small fan on low for 30 minutes a day will thicken stems noticeably within 3–4 days

Gray or white fuzzy mold appearing on the substrate surface or at the base of stems, usually days 5–10

Likely Causes

Botrytis cinerea or common surface mold from overwatering and poor air circulation
Top-watering the canopy directly — it soaks the stems and creates the humidity mold needs to take hold

What to Do

1.Switch exclusively to bottom-watering: set the tray in a shallow pan of water for 10–15 minutes, then drain completely
2.Run a fan near the trays to keep surface air moving — even intermittently helps
3.If mold is already established, harvest immediately whatever looks clean; a fully affected tray isn't worth saving

Tiny dark flies hovering around trays, seedlings wilting or stunted despite adequate moisture

Likely Causes

Fungus gnats (Bradysia spp.) — their larvae feed on root hairs in moist substrate, which collapses young seedlings fast
Old or contaminated growing medium that wasn't pasteurized or was stored wet

What to Do

1.Let the top half-inch of substrate dry out between waterings — fungus gnat larvae can't survive without consistent surface moisture
2.Set yellow sticky traps at tray level to catch adults and confirm the ID before treating
3.Start fresh with a clean, sterile substrate (coconut coir or a purpose-made microgreen mix) and sanitize trays with a 10% bleach solution between cycles

Frequently Asked Questions

How long does Evergreen Hardy White scallion microgreen take to grow?▼

Evergreen Hardy White typically reaches harvest maturity in 16-25 days from sowing. Germination occurs within 7-10 days, followed by 6-15 days of leaf development depending on temperature and light. Cooler temperatures (60-65°F) extend the timeline slightly but intensify flavor. Warmer conditions (70°F+) accelerate growth. Most growers harvest at the 20-22 day mark for optimal balance of flavor, texture, and yield.

Can you grow Evergreen Hardy White scallion microgreens in containers indoors?▼

Yes, absolutely. Evergreen Hardy White is ideal for indoor container growing. Use standard 10×20-inch microgreen trays or any shallow container 1.5-2 inches deep with drainage. Place under grow lights or in a bright window with 4-6+ hours of light daily. Maintain 60-70°F temperatures. This variety thrives indoors year-round, making it perfect for apartments, kitchens, or controlled growing spaces where outdoor growing isn't feasible.

What does Evergreen Hardy White scallion microgreen taste like?▼

Evergreen Hardy White offers a delicate, mild onion flavor with subtle pungency—noticeably gentler than standard mature scallions. The taste is refined and sophisticated, adding a whisper of allium character without overpowering. The tender, green thread-like leaves contribute a fresh, slightly sweet quality. This makes it ideal for garnishing soups, salads, Asian dishes, and plated restaurant presentations where restraint is preferred over bold onion bite.

Is Evergreen Hardy White good for beginner microgreen growers?▼

Yes, it's an excellent beginner variety. It germinates reliably, tolerates minor watering inconsistencies better than finicky varieties, and grows quickly. Its hardy nature means it's forgiving of cooler room temperatures and lower light conditions that might stress other microgreens. The main challenge is its delicate texture and short shelf life, but for home gardeners harvesting for immediate use, these are non-issues.

Can Evergreen Hardy White scallion microgreens be grown outdoors?▼

Yes. Its hardy genetics make it one of the few microgreen varieties suited to outdoor production, especially in cool seasons or mild climates. Sow in shallow trays or flats outdoors in spring or fall for extended growing seasons. It tolerates light frost, making fall harvests possible well into winter in moderate climates. Provide some afternoon shade in hot climates to prevent bolting and maintain tenderness.

What's the difference between Evergreen Hardy White and other scallion microgreen varieties?▼

Evergreen Hardy White is distinguished by its exceptional cold hardiness, allowing year-round outdoor and unheated indoor production. Its flavor is milder and more refined than aggressive varieties like Bunching White, making it preferred by chefs. It also germinates slightly faster and produces denser yields per tray. Other varieties may offer larger plants or more pungent flavor, but Evergreen Hardy White excels in reliability, versatility, and culinary sophistication.