From sugar cane to sugar beets

By 1812 conversion to sugar beets had reached 15 sugar refineries in Antwerp.4 However, after the blockade was lifted, most refineries turned back to sugar cane, which I find hard to grasp as beet sugar can be derived from a homegrown product, thereby avoiding import duties. But those import duties were lowered in the years after the blockade, and the number of sugar refineries grew again to at least 50 in 1833, only to fall back to 36 one year later.4 Germany had closed its borders for sugar and was producing its own sugar from sugar beets (see Lebkuchen).