Garlic vs onion os

If you are trying to decide between planting garlic and onion sets, the answer depends on your space, climate, and patience. Garlic is a low-maintenance fall crop with a long storage life, while onion sets give you a faster spring harvest but need more attention to day length and watering. Here is the direct comparison: garlic is easier for beginners and yields more per square foot, but onions are quicker to mature and offer more variety in fresh eating. Choose garlic if you want a set-and-forget crop; choose onions if you want to harvest in early summer and have fresh bulbs for salads.

Planting Time and Climate

Garlic is planted in fall, about 4 to 6 weeks before the ground freezes. In USDA zones 3 to 5, that means late September to mid-October. Zones 6 to 8, plant in October to November. Zones 9 to 10, plant in late November to December. Onion sets are planted in early spring, as soon as the soil can be worked, usually March to April for zones 5 to 7. In warmer zones, you can plant in February or March.

Garlic needs a cold period (vernalization) to form bulbs, so it must go through winter. Onions are day-length sensitive: short-day varieties for the South (zones 7 and warmer), long-day for the North (zones 6 and cooler), and intermediate for the middle. If you plant the wrong type, you get leaves but no bulbs.

Spacing and Soil Preparation

Both crops need well-drained soil with a pH of 6.0 to 7.0. Work in 2 inches of compost before planting. For garlic, break the bulb into cloves and plant each clove 2 inches deep, pointy side up, with 6 inches between cloves and 12 inches between rows. For onion sets, plant the sets 1 inch deep, with 4 inches between sets and 12 inches between rows. Garlic is a heavier feeder: mix in a balanced fertilizer like 10-10-10 at planting, about 1 pound per 50 square feet. Onions need nitrogen early, so side-dress with blood meal or fish emulsion when tops are 6 inches tall.

Varieties to Choose

For garlic, choose hardneck types for colder zones (zones 3 to 6) because they produce scapes and have richer flavor. Try ‘Music’ or ‘German Extra Hardy’. Softneck types like ‘California Early’ or ‘Inchelium Red’ are better for zones 7 to 10 and store longer. For onions, long-day varieties for the North: ‘Yellow Sweet Spanish’ or ‘Walla Walla’. Short-day for the South: ‘Texas SuperSweet’ or ‘Red Creole’. Intermediate: ‘Candy’ or ‘Superstar’.

Care and Maintenance

Garlic needs consistent moisture in spring, but stop watering when the lower leaves start to yellow, usually in June. Mulch with straw to suppress weeds and retain moisture. Onions have shallow roots, so they need regular watering, about 1 inch per week. Keep the soil evenly moist, but not soggy. Weed by hand or with a hoe, but be careful not to disturb the bulbs. For garlic, remove scapes (the curly flower stalks) in late spring to direct energy to the bulb. For onions, do not bend the tops; let them fall naturally.

Harvest and Storage

Garlic is ready when the lower leaves turn brown, usually 8 to 9 months after planting. In zones 5 to 7, that is late June to July. Dig carefully with a fork, then cure in a dry, airy place for 2 to 3 weeks. Trim roots and tops, then store in a cool, dark place (50 to 60°F) for up to 8 months. Onions are ready when the tops fall over, about 100 to 120 days after planting sets. Pull them on a dry day, cure for 2 to 3 weeks in a well-ventilated area, then braid or store in mesh bags. Sweet onions store only 1 to 2 months, while pungent types can last 6 months.

Cost and Yield Comparison

Crop	Cost per 100 plants	Yield per 10 feet row	Storage life
Garlic (cloves)	$15 to $25	10 to 15 bulbs	6 to 8 months
Onion sets	$10 to $15	20 to 30 bulbs	1 to 6 months

Garlic costs more upfront but yields fewer bulbs per row. Onions are cheaper and produce more, but they take more water and attention. In 2026, a pound of garlic seed cloves costs $12 to $18, while a pound of onion sets (about 100 sets) costs $8 to $12. You can also grow from seed, but that adds 8 to 10 weeks of indoor starting.

Common Pests and Problems

Garlic has few pests, but onion maggots can attack both. Use row covers to prevent flies from laying eggs. Fusarium rot is a risk in wet soil, so rotate crops and avoid overwatering. For onions, thrips are a problem in hot, dry weather; spray with neem oil if you see silver streaks on leaves. Both crops can suffer from bolting if temperatures fluctuate; choose bolt-resistant varieties like ‘Red Burgundy’ for onions.

FAQ

Can I plant garlic and onions together?

Yes, they are compatible, but give them separate beds because they have different watering needs. Garlic is drought-tolerant once established, while onions need steady moisture.

How do I know when to harvest garlic?

When the lower 3 to 4 leaves turn brown, dig up one bulb to check. If the cloves fill the skin, it is ready. Do not wait too long or the bulbs split.

Why are my onions not forming bulbs?

You likely planted the wrong day length for your zone. Check if you need long-day or short-day varieties. Also, onions need full sun and consistent moisture.

Can I grow garlic from grocery store bulbs?

It is possible, but grocery bulbs may be treated to prevent sprouting. Better to buy seed garlic from a nursery for disease-free, adapted varieties.

The Bottom Line

Both garlic and onion sets are worth growing, but garlic is the lower-maintenance choice for most gardeners. Plant garlic in fall, water in spring, and harvest in summer with minimal fuss. Onions give you a quicker crop but require more attention to day length and watering. If you have room, grow both: garlic for storage and onions for fresh eating. Start with garlic if you are new to alliums, then add onions once you have the rhythm down.