Using Vegetables, Vegetable Tubers and roots for beverages is a little bit weird but not uncommon. Sugar beet (molasses) and potatoes are used for vodka and neutral spirits. Potatoes need an addition of Amylase-enzyme.
Gentian spirit and Topinambour spirit are somewhat special. They are made of the roots only and need special processing and addition of enzymes too. Gentian doesn’t contain glucose or fructose but a sugar called gentianose which the yeast can’t ferment or at least very slowly. This sugar needs to be converted by enzymes first.
Topinambour (Jerusalem artichokes) contain Inulin which is very healthy in your diet but also unfermentable by yeast. This carbohydrate must be converted to fructose by enzymes.
Some homemade „Fruitwines“ are known from vegetables like beetroot, carrot and parsley. But garlic and onions too. Such beverages are not allowed to be produced commercially.
Rhubarb wines (from the stems) are known as well and in some countries commercially made.
Tomatoes are also used for fruitwine making, botanically they are fruits and not vegetables.
Manioc is used for beermaking in Brazil and Cassava in South America and Africa. Both roots are toxic and contain cyanide. Special processing is required before it’s safe to eat. The enzymatic procedure mentioned in this post is also used here before fermentation by yeast can take place.
other roots like ginger are also used for beverages like root beer or ginger ale (lemonade)
and others for flavouring liqueurs, cordials and spirits