Kaiser Wilhelm is a high yielding variety with long, off-white tubers. I think it has the best combination of tuber size, yield, and flavor of the heirloom dahlias that we have tested. The tubers are firm and juicy and quite sweet when raw. The flower is a large orange and yellow ball. We also have a single flowered mutant which I use for seed production. I assume that the single flowered form is a somatic mutant and so the seeds will not transmit that trait in excess of the usual ball form, but I’m not entirely sure of that. Large plants grow to about four feet.
This is a very old variety, dating to 1881. It seems that older varieties are a little more likely to make good edibles, possibly because they haven’t been selected as long and intensively for flower traits.
Although we sometimes offer tubers of these varieties, my main focus is producing seed for breeding. Like all dahlia seeds, the true seeds of this variety will not be true to type. I have grown out quite a few and got a range of types, predominantly single flowered and ball types. Many of them have tubers with good edible qualities.