This is probably the best known of all mashua varieties outside the Andes, although as an ornamental, rather than an edible. It was reportedly discovered by its namesake at the Royal Horticultural Society garden at Wisley, UK as a volunteer seedling in the 1950s. It was available in the US as early as 1978. Although the specifics of its origin are lost to history, based on its appearance, I imagine the parent was a Peruvian variety of the type that is called “tears of blood”. It is often claimed to be a day neutral variety, but I would describe it more as an intermediate daylength variety. It does flower and form tubers earlier than most other mashua varieties, but that means late summer rather than early fall. If planted very early, in February or March, it will sometimes flower in spring, although it usually stops and then resumes in summer. It appears to initiate flowering at day lengths below 14 hours.
Ken Aslet is a pungent variety, with a flavor like horseradish pickled in cheap perfume. Although thorough cooking mellows it to a more turnip-like taste, you shouldn’t buy this one for its fine flavor. Instead, grow Ken Aslet because it is a nice ornamental edible that is beloved by hummingbirds or so that you can breed its earlier tuberization into better tasting mashuas. Tubers are cream to yellow with red eyes and striations. Tuber size ranges from less than an inch to about nine inches, but most are in the two to four inch range. Fasciation is common in this variety, possibly a sign that it is infected with a virus, although I have done my best to clean it up, so it could be a genetic predisposition. Ken Aslet is rather low yielding for mashua, although that only matters if you are going to eat it.