White Grano PRR

Family: Amaryllidaceae Vegetable

Crisp, luminous bulbs with a clean, white sheen—White Grano PRR brings a bright, sweet-on-the-palate character that turns wonderfully mellow in the garden’s first cool nights.

Expect a firm, medium-to-large globe with a tight, dry outer skin and a satisfying snap when you break it open, making it a favorite for fresh slicing, roasting, and slow-simmered sauces. Grow for dependable, 95-day performance and a harvest that stores with confidence, ready whenever your table calls for gentle allium sweetness.

Light: Full SunMaturity: 95 DaysHabit: Bulbing

Botanical illustration of White Grano PRR

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

Crop Dates

Milestone	Date
Start Indoors	Feb 28th
Last Frost	Apr 25th
Transplant / Sow Outdoors	Apr 18th
Harvest Begins	Jul 22nd
Harvest Ends	Oct 16th

Crop Details

Trait	Value
Days to Maturity	95
Sun Requirements	Full Sun
Growth Habit	Bulbing
Support Needed	None
Planting Depth	Normal
Germination Temp (°F)	75
Min Soil Temp (°F)	45
Min Night Temp (°F)	35
Harden Off (days)	7

Culinary Notes

Chef's Note

White Grano PRR keeps its structure—great for slicing without going limp—and its sweetness mellows fast under heat into a jammy, caramel-adjacent onion base. It’s the kind of onion that earns its keep in sauces where you want flavor that rounds off, not stings.

Best Uses

thin raw slices for crunchy, clean sweetness on sandwiches and salads
roasting until edges caramelize for soft, spoonable tenderness
slow-simmered sauces and braises where you want sweetness without harshness

Flavor Profile

bright, sweet-on-the-palate bite firm, crisp snap with juicy layers turns mellow and jammy when gently cooked

Kitchen Pairings

olive oil thyme butter gruyère beef stock cabernet sauvignon

Frequently Asked Questions

What is a common pest or disease for Allium cepa (white onions), and how can I fix it at home?

One of the most common issues is onion thrips, which cause silvery streaks and distorted, weakened leaves. Start by keeping weeds down and removing heavily damaged leaves early; for control, spray the foliage with insecticidal soap and repeat every 5–7 days for 2–3 cycles, covering leaf undersides. If you notice pinkish fungal growth or soft, rotting bulbs near harvest, discard affected plants and avoid replanting onions in the same soil for a few years.

How often should I water Allium cepa during the main growing phase?

During active leaf and bulb growth, keep the soil consistently moist but not waterlogged—aim for about 1 inch of water per week, adjusted for heat and rainfall. Water deeply 1–2 times per week rather than a little every day, and stop frequent irrigation as bulbs start to swell to prevent soft rot and splitting. Use a simple check: the top 1–2 inches of soil should be moist, not soggy, before the next watering.

How do I tell when Allium cepa is ready to harvest (for ~95 days)?

Harvest when about 50–70% of the tops have flopped over and the necks start to dry down, usually around your ~95-day maturity. Lift a sample bulb to check skin quality—papery white skins should be fully formed and the bulb feels firm. Cure onions by drying them in a warm, airy spot for 1–2 weeks, then trim tops to about 1–2 inches for storage.