Allium cepa var. aggregatum
Origin: Colorado
Improvement Status: Grex/Breeding material
Seeds per packet: ~40
Germination tested 10/2024: 86%
Life cycle: Perennial
EFN EXCLUSIVE. Kelly Winterton of Utah created the original 'Green Mountain Multiplier' following a chance flowering of his perennial potato onions (Allium cepa var. aggregatum). Potato onions are a lot like shallots, only they keep for much longer and are generally fleshier and without the purple pigmentation in each layer. The main disadvantage compared to standard biennial onions is their small size. Kelly's potato onions flowered after being overwintered in the ground outdoors, rather than being stored inside and replanted in the spring. The seedlings proved to be incredibly diverse, and some of them paired the best traits of potato onions with sizes closer to a supermarket onion.
Some of Kelly's onions made their way to EFN grower Andy Hahn in Colorado, who last year produced a bumper crop of true seed — and at the same time as his yellow potato onions happened to be flowering. The resulting seed is what we're proud to be offering here. Every seedling will be unique, so each will be something new. We urge anyone who orders this seed to sign up to the Perennial Dividing Onion Diversification project on the main EFN website.
There's been a lamentable loss of potato onion varieties over the past century, such that old heirlooms are now incredibly hard to come by (we maintain just one, a yellow/brown-skinned type from the former East Germany known as 'Strausberger Gelbe'). Kelly's work, furthered by Andy, has the potential to produce countless new potato onion varieties. Their perennial growth habit and long-storing ability will make these new varieties valuable to anyone looking to become independent from the supermarket.
Start these seeds early if you can, and you'll be well on your way to nurturing your own new easy-to-grow staple crop. And when you find that perfect new variety, give it a name and start spreading it around!
GROWING TIPS: Start in flats as early as possible (February or March). Transplant to a well-prepared bed once seedlings are a few inches tall and sturdy enough to stand up to the weather. Keep an eye on them throughout the season as they will likely ripen at different times. Bulbs can be removed from the ground once the leaves are no longer green. You may also want to leave some bulbs in the ground to see if they will perennialize in your area. If you've never grown potato onions before, you'd be wise to do some internet sleuthing to learn what to expect!
