Cabernet

Onion

110d to harvest

Aromatically pungent at first touch, Cabernet onions mature into handsome bulbs with a deep, wine-toned skin that glows under garden light. The flesh is crisp and finely layered, offering a balanced bite that turns sweet and mellow when coaxed into its best form—ideal for roasting, sautéing, and slow-simmered sauces, as well as for fresh slicing when you want a lively allium snap. Grow Cabernet for its dependable intermediate-day timing and its striking, richly colored bulbs that store with confidence for weeks of flavorful use.

Crop Dates

Growing note: Zone 3a has only 109 frost-free days — shorter than this crop's 110-day maturity. Outdoor planting is not viable; use protected cultivation.

Milestone	Date
Last Frost	May 15th
Growing Approach	Protected Environment Only

Crop Details

Trait	Value
Days to Maturity	110
Sun Requirements	Full Sun
Growth Habit	Bulbing
Support Needed	None
Planting Depth	Normal
Germination Temp (°F)	70
Min Soil Temp (°F)	45
Min Night Temp (°F)	28
Harden Off (days)	7

Frequently Asked Questions

What pest or disease most commonly affects Allium cepa (onions) like Cabernet, and what can I do?

Onions (Allium cepa) are commonly affected by purple blotch (Alternaria porri), which shows as purple-gray spots on leaves and can spread in humid weather. Start with clean, well-spaced plants and water at the soil line to keep foliage dry; remove badly spotted leaves early. If it becomes severe, apply a labeled fungicide that targets Alternaria/leaf blight and repeat according to the label during active disease pressure.

How often should I water Cabernet onions during the main growing phase, and how moist should the soil stay?

During bulb formation (the bulk of the ~110 days), keep the soil evenly moist but not soggy—aim for about 1 inch (2.5 cm) of water per week, split into 1–2 waterings depending on heat and rainfall. Let the top 1–2 inches (2.5–5 cm) of soil dry slightly between waterings to avoid bulb rot. Mulch lightly to stabilize moisture, and stop watering as bulbs mature to improve keeping quality.

How do I tell when Cabernet onions are ready to harvest?

Harvest when about 50–75% of plants have naturally fallen over and the necks are starting to dry down, not when you “just feel” the bulb size. Lift bulbs carefully to avoid bruising, then cure them in a warm, airy spot out of direct sun until the outer skins are dry and papery (usually 1–2 weeks). If the neck is still soft or the skin won’t crack dry, give them more curing time before storage.

Recommended Companions

Cabernet

Planting Schedule

Crop Dates

Crop Details

Frequently Asked Questions

Recommended Companions