SproutSmart
SproutSmart Intelligent Garden Sowing

Red Zeppelin

Onion
Botanical illustration of Red Zeppelin
🌱 110d to harvest Bulbing

Aromatically pungent at first touch, Red Zeppelin forms handsome, deep garnet-red bulbs that hold their color with a confident, g…

Planting Schedule

Add Red Zeppelin to your garden to build a schedule and get reminders.

Crop Dates

MilestoneDate
Start IndoorsFeb 9th
Last FrostMar 23rd
Transplant / Sow OutdoorsMar 16th
Harvest BeginsJul 4th
Harvest EndsNov 12th

Crop Details

TraitValue
Days to Maturity110
Sun RequirementsFull SunFull sun
Growth HabitBulbing
Support NeededNone
Planting DepthNormal
Germination Temp (°F)70
Min Soil Temp (°F)50
Min Night Temp (°F)35
Harden Off (days)7

Frequently Asked Questions


What pest or disease is most likely on Allium cepa (red onion) and how can I prevent it?
Watch for onion thrips and downy mildew, which are common on Allium cepa. Use preventive sprays only if needed: remove any infected leaves early (yellowing tips or fuzzy gray/whitish growth), keep foliage dry by watering at the soil line, and rotate onion family crops so they’re not grown in the same bed for at least 3 years. If you see thrips, use insecticidal soap and target the undersides of leaves, repeating as new growth appears.
How often should I water Allium cepa during the main growing phase?
During active leaf growth and bulb sizing, keep the soil evenly moist but not waterlogged—about 1 inch of water per week, split into 2–3 waterings if it’s hot or windy. Check moisture: the top 1–2 inches should be moist, but the bed should drain well. Stop frequent watering once most tops start to yellow and fall over so the bulbs can dry and cure.
How do I tell when red onions (Allium cepa, Red Zeppelin type) are ready to harvest?
Harvest when about half of the tops have flopped over and the necks are thinning, with dry, papery skins covering the bulb. Gently lift one or two plants to confirm bulb size matches your expected mature diameter and that skins are fully colored. Choose a dry day, then cure bulbs in a warm, airy place out of direct sun for about 2–3 weeks before storage.
Botanical illustration of Red Zeppelin

Aromatically pungent at first touch, Red Zeppelin forms handsome, deep garnet-red bulbs that hold their color with a confident, glossy sheen. The flesh is crisp and well-layered, offering a balanced bite that sweetens beautifully when cooked down and shines in fresh preparations. Ideal for intermediate-day gardeners seeking reliable bulbing and long-lasting storage, Red Zeppelin is a standout for hearty sauces, roasting, and pickling-style preserves.

Sowing Tips

Transplant Conditions

Wait until soil reaches 50°F and nights stay above 35°F before moving outdoors. Harden off for 7 days first.

Expert Note

For storage onions, aim for firm bulbs by keeping soil evenly moist early and then gradually reducing watering as tops begin to yellow.