Yellow storage onions on wood surface – best onion seeds to buy for vegetable gardens

Onion Seeds: Best Place to Buy Garden & Vegetable Seeds Online for Big Harvests

Onions may be one of the most important vegetables you ever grow. From long-storage winter keepers to sweet slicing onions for summer meals, onion seeds give home gardeners the widest planting options, best disease resistance, and highest yields. Whether you garden in raised beds, rows, or containers, growing onions from seed offers superior performance over buying onion sets at the store — and once you start, you’ll never go back.

This guide covers the best onion seeds for home gardens, how to grow onions successfully from seed, and where to buy high-quality onion seeds online — including small packs for backyard gardeners and bulk quantities for market growers.


Why Grow Onions From Seed Instead of Buying Sets?

Most store-bought “onion sets” are last year’s leftover bulbs. They bolt early, don’t size up well, and produce inconsistent results.

Growing onions from seed gives you:

Bigger bulbs
More varieties (sweet, red, storage, short-day, long-day)
Better disease resistance
No early bolting
Lower cost and higher yield

A single onion seed packet can grow hundreds of onions — making it one of the most productive crops per square foot in any vegetable garden.


Best Place to Buy Onion Seeds Online

Quality seed matters. To grow problem-free onions that size up properly, you need fresh seed from a reliable source — not chain store leftovers.

At Trailing Petunia, you can buy onion seed packs in both home garden sizes and bulk farm-quantity packs:

🧅 BUY ONION SEEDS – REGULAR SIZE PACKS

Perfect for raised beds, container gardens, and backyard growers:
👉 https://www.trailingpetunia.com/search?q=onion&options%5Bprefix%5D=last

🧅 BUY ONION SEEDS IN BULK

Ideal for CSA farms, homesteads, and large garden plots:
👉 https://www.trailingpetuniabulkseeds.com/search?q=onion&options%5Bprefix%5D=last

Need additional seed categories?

🌱 Smaller Packs – All Garden Seeds
👉 https://www.trailingpetunia.com

🌾 Bulk Packs – All Vegetable & Flower Seeds
👉 https://www.trailingpetuniabulkseeds.com/


Best Onion Types for Home Gardeners

Choosing the right onion depends on your region and storage needs:

🟡 LONG-DAY ONIONS

Best for Northern climates
Bulbs form when day-length reaches 14+ hrs
Examples: Yellow Sweet Spanish, Walla Walla, Ringmaster

🔴 SHORT-DAY ONIONS

Best for Southern growers
Bulbs form when day-length reaches 10–12 hrs
Examples: Texas Early Grano, Red Creole, Southern Belle

🧅 INTERMEDIATE DAY

Work across most U.S. regions
Reliable storage + slicing option
Examples: Candy Onion, Red Zeppelin


How to Grow Onions From Seed (Step-by-Step)

🔥 Start Indoors Early
Begin 10–12 weeks before your final frost date
Ideal soil temp: 65–75°F

🌱 Transplant Outdoors When Soil is Workable
Onions are cold hardy — they tolerate light frost

📏 Proper Spacing = Bigger Bulbs
4" apart for full-sized onions
2" apart for “mini onions”

💧 Water Consistently
Uneven watering → split or puny bulbs

Harvest When Tops Fall Over
Cure in a warm shaded location for storage

📌 Best Eggplant Seeds for Home Gardens | Where to Buy High-Quality Vegetable Seeds Online
https://www.trailingpetunia.com/blogs/news/best-eggplant-seeds-for-home-gardens-where-to-buy-high-quality-vegetable-seeds-online


FAQ – Growing Onions From Seed

Q: Are onions hard to grow from seed?
No — they are slow-growing, but simple if started early.

Q: How many onion plants do I need?
Plan 30–50 plants per person for year-round onion supply.

Q: Can onions be grown in containers?
YES — use compact varieties and plant densely for mini bulbs.

Q: Do onions need full sun?
Yes, 6+ hours is required for proper bulb development.

Q: Can I direct sow onions?
Yes — but indoor transplanting leads to bigger bulbs and earlier harvests.

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