SproutSmart
SproutSmart Intelligent Garden Sowing

Red Amposta · Onion

Zone 4b Save Garden

Planting Schedule

Add Red Amposta to your garden to build a schedule and get reminders.
MilestoneDate
Start IndoorsMar 4th
Last FrostMay 13th
Transplant / Direct Sow OutdoorsMay 13th
Harvest BeginsAug 16th
Harvest EndsSep 27th

Crop Details

Transplant Conditions: Wait until soil reaches 45°F and nights stay above 35°F before moving outdoors. Harden off for 7 days first.
TraitValue
Days to Maturity95
Sun RequirementsFull 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
Expert Note: For the sweetest “red storage-type” bulbs, grow with consistent moisture and avoid nitrogen-heavy feeding once bulbs begin to swell.