SproutSmart
SproutSmart Intelligent Garden Sowing

Yellow Granex

Family: Amaryllidaceae Vegetable

Planting Schedule

Add Yellow Granex to your garden to build a schedule and get reminders.

Golden warmth spills from every Yellow Granex bulb—sweet, mellow flavor with a gentle bite that lingers like sun on skin.

At maturity, the bulbs form broad, flattened globes with crisp, papery outer layers and a dense, juicy interior that stays tender and slice-ready. Grow Yellow Granex for reliable harvests around 90 days, ideal for fresh use, roasting, and caramelizing into rich, golden sauces.

Light: Full SunMaturity: 90 DaysHabit: Bulbing

Botanical illustration of Yellow Granex

Planting schedules and alerts are optimized for Columbus (Zone 6b).

Crop Dates

MilestoneDate
Start IndoorsFeb 14th
Last FrostApr 25th
Transplant / Sow OutdoorsApr 18th
Harvest BeginsJul 17th
Harvest EndsOct 16th

Crop Details

TraitValue
Days to Maturity90
Sun RequirementsFull SunFull sun
Growth HabitBulbing
Support NeededNone
Planting DepthNormal
Germination Temp (°F)70
Min Soil Temp (°F)40
Min Night Temp (°F)35
Harden Off (days)7

Culinary Notes


Chef's Note

Yellow Granex brings a sweeter profile than sharp storage onions, so it browns fast without going acrid. Use it when you want tender slices that caramelize into glossy strands—or roast until the edges crisp and the center turns almost custardy.

Best Uses

  • caramelizing into jammy, golden strands without turning bitter
  • roasting for soft-center sweetness and browned edges
  • fresh use in salads where you want mellow onion impact
  • slow-reduced pan sauce base that turns silk-golden

Flavor Profile

sweet, mellow onion flavor gentle bite with a clean, lingering allium finish juicy, slice-friendly interior with firm layers

Kitchen Pairings

butter thyme balsamic vinegar beef or pork Gruyère black pepper

Frequently Asked Questions


What pest or disease commonly affects Allium cepa (yellow onions), and how can I stop it?
Onion thrips can cause silvery streaking and distorted onion leaves, especially in warm, dry spells. Check plants weekly and spray insecticidal soap or spinosad according to label directions; keep weeds down because they host thrips. If you see soft, rotting bulbs or purple-gray mold at the neck, remove affected plants immediately and improve airflow—onions in wet, crowded beds develop neck rot and other fungal issues.
How often should I water Allium cepa during the main growing phase (bulb formation)?
During bulb formation, keep soil consistently evenly moist but not soggy—about 1 inch of water per week, adjusting for heat and rainfall. Water deeply to reach the root zone, then let the top 1–2 inches of soil dry slightly before watering again. When about 10–20% of the tops begin to fall over near the end of the 90-day cycle, reduce watering to help bulbs cure and prevent watery rot.
How do I know when Allium cepa (yellow Granex-style onions) are ready to harvest?
Harvest when plants reach roughly 90 days from planting and most tops have turned yellow and started to fall over, with dry, tight necks. Gently lift one or two bulbs to confirm the skin is papery and bulbs are fully sized. Leave onions in place to cure for a short period with good airflow, then cure longer indoors out of direct sun if weather is humid.