The ‘normal’ form of this plant in western cultivation is a short-day plant, meaning that it only gets down to flowering and making new tubers once the days are becoming shorter, later in the season.
Ken Aslet is a day neutral form thus it flowers earlier and peaks sooner, and you can expect lovely, large yellow and red-orange, "Nasturtium" blooms, from early summer onwards.
It can also be lifted and stored dry over winter for safety – like a potato. Also like that plant, it can be baked or dried and powdered, if you don’t like the flowers after all!
Sunny well drained soil in full sun.