onion seeds for planting Sapelo Sweet Onion Seed | Jumbo Sweet Onions

onion seeds for planting Sapelo Sweet Onion Seed | Jumbo Sweet OnionsWhy Grow Sapelo Sweet Onion? Jumbo Onion Bulbs The Sapelo Sweet Onion is a hybrid, short day onion that delivers colossal size, exceptional yields, and outstanding flavor. This large Granex type onion features a 2: 1 bulb ratio, light bronze skin, and firm, wide interior rings that are perfect for slicing. With dark green tops, 78 sturdy leaves, and a high percentage of jumbo bulbs, its one of our most productive onion varieties. Size, Yield, and

Why Grow Sapelo Sweet Onion?

Jumbo Onion Bulbs The Sapelo Sweet Onion is a hybrid, short-day onion that delivers colossal size, exceptional yields, and outstanding flavor. This large Granex-type onion features a 2:1 bulb ratio, light bronze skin, and firm, wide interior rings that are perfect for slicing. With dark green tops, 7–8 sturdy leaves, and a high percentage of jumbo bulbs, it’s one of our most productive onion varieties.

Size, Yield, and Quality Sapelo Sweet reaches mid-season maturity and offers moderate tolerance to Pink Root, making it a reliable performer in a wide range of growing conditions. Sapelo Sweet also stores well, allowing you to enjoy your harvest for an extended period. Whether you’re planting for fresh market sales or your own kitchen, this variety combines size, yield, and quality into one impressive package—making it a must-have choice for serious onion growers.

Sapelo Sweet Onion Growing Tips

• When to Plant Short-Day Onions

Short-Day onion varieties are ideal for the southern states and will usually start bulbing when the day length reaches 10-12 hours in the spring. Onions are typically cold hardy to 20°F, but we've seen them survive temperatures as low as 17°F. If you rarely experience temperatures in the low 20s, you'll want to transplant short-day onions in the fall and overwinter them. If you frequently experience temperatures in the low 20s and below, you'll want to wait until late winter to transplant your onions.

Onions usually take about 5-6 weeks to go from seed to viable transplant. Figure your ideal planting date and count back 5-6 weeks to determine when you should start onion seeds in your greenhouse or seed starting room. Onion seeds will germinate best at soil temperatures around 70°F and usually take 8-10 days to germinate. If the soil temperature is not ideal, they can sometimes take two weeks to germinate.

• How to Fertilize Onions

Onions are heavy feeders. Give them plenty of water and nutrients and you'll grow some big ones! We recommend applying our Coop Gro Fertilizer in the planting furrow at transplanting. This will provide the phosphorous and potassium that the young onion plants need to develop a strong root system.

Once the onion plants get approximately 1' tall, side dress them with a high nitrogen fertilizer. We usually side dress our onions 1-2 times during the vegetative phase when they're producing all that luscious green growth. You'll want to maximize the green growth during this vegetative phase because this is what will help produce a large onion during the bulbing phase.

• When to Harvest Onions

Onions should be harvested when the tops start to fall on the ground, or when the tops start to dry and wither. In some cases, the tops will lean and fall on the ground as the plant stops devoting energy to the leaves. In other cases, the tops may not fall but will slowly wilt down to nothing.

Once you see either happening, go ahead and pull the onions and allow them to "cure" or dry. We like to cure ours in the full sun on the soil or grass, but others prefer to cure them in a cooler area. The goal is get the leaves and roots to dry so that the onion stores well.

To see more great onion growing tips, see this blog or watch this video.