SproutSmart
SproutSmart Intelligent Garden Sowing

Red Burgermaster

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

Crisp, sweet-scented bulbs with a bold, wine-red outer skin—Red Burgermaster brings a striking color and a satisfying bite to the…

Planting Schedule

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

Crop Dates

MilestoneDate
Start IndoorsDirect Sow
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)45
Min Night Temp (°F)35
Harden Off (days)7

Frequently Asked Questions


What’s a common disease problem for Allium cepa (red onions), and how do I prevent and treat it?
Onions frequently suffer from downy mildew (often seen as gray-purple growth on leaves) and fungal leaf blights, especially in cool, damp weather. Improve airflow by spacing plants and watering at the soil line, then remove and discard infected leaves. If disease pressure is high, apply an onion-labeled fungicide and repeat according to the label to protect new growth before the next rainy cycle.
How often should I water Allium cepa during the main bulbing phase?
During bulbing (once plants are well established), keep soil evenly moist but not waterlogged—about 1 inch of water per week total, adjusted for heat and rainfall. Let the top 1–2 inches of soil dry slightly between waterings, because constantly wet soil encourages rot and weak bulb formation. Stop regular watering about 10–14 days before harvest to help skins dry and bulbs cure properly.
How can I tell when red onions (Allium cepa) are ready to harvest?
Harvest when about 50–70% of the tops have fallen over and the necks feel soft but not actively wet, typically around the 110-day mark. Bulbs should have well-formed skins with good color and a papery outer layer. Lift on a dry day, leave tops on to cure in a warm, airy spot for about 1–2 weeks, and avoid harvesting if rain is expected right after.
Botanical illustration of Red Burgermaster

Crisp, sweet-scented bulbs with a bold, wine-red outer skin—Red Burgermaster brings a striking color and a satisfying bite to the home garden. The flesh is clean and bright, with a gentle sweetness that turns mellow when roasted and shines in fresh preparations, from hearty salads to vibrant relishes and savory sauces. Grow it for its substantial, burger-worthy size and its reliable, storage-minded performance at about 110 days to maturity.

Sowing Tips

Transplant Conditions

Wait until soil reaches 45°F and nights stay above 35°F before moving outdoors. Harden off for 7 days first.

Expert Note

For the sweetest, best “grill-slice” bulbs, keep plants evenly watered and avoid heavy nitrogen once bulbs begin to swell.