Know your Potato Onion
Know your Potato Onion - Introduction
The potato onion (Allium cepa L. var. aggregatum) is a variety of multiplier onion, similar to the shallot, although producing larger bulbs.
It is remarkably easy to grow, keeps better than almost any other variety of onion, and is ideal for the home gardener with restricted space.
It was very popular in the past, but like many old varieties, it has been passed over in favour of types more suitable for mechanical harvesting and mass marketing.
The onions vary in size from 1 - 8cm (half an inch to three inches) in diameter.
Know your Potato Onion - Cultivation
The potato onion rarely produces seeds, so it is propagated by the small bulblets or bulbs which are formed underground.
When a strong bulb is planted it forms a number of smaller bulblets, each with a leafy top.
However, a weak bulb generally grows into a single large bulb.
The culture is similar to that for regular onions.
Space 4-6 inches to allow for the clumps to form.
Sources differ about planting depth, some saying shallow planting is appropriate and others calling for deeper planting. This onion does tend to grow very close to the surface and a planting hole perhaps 2.5cm (1 inch) deeper than the diameter of the bulb seems to work well.
Most sources say it should be planted in the autumn, but this probably applies only to areas with moderate climates.
It can be planted in the spring as early as the ground can be worked and produces well when so planted, up to at least the most northern limits of planting zone 5.
Know your Potato Onion - Culinary Uses
Pull individual green onions as soon as the bulbs are large enough for eating.
Green immature onions may be used fresh like any type of bunching onion.
More mature bulbs may be used in cooking after the outer scales are removed.
