One of their top crops is red vein sorrel, prized for its tart citrus flavor and dramatic red-veined leaves. Occupying about 25 percent of the vertical farm, it’s a favorite among chefs for its ...

Red-vein sorrel is a decorative variety with red stems and veins, and the slightly bitter leaves can also be used straight in a mixed salad. Water in dry weather to avoid the leaves becoming too ...

Some groceries can live on well after the shopping is done. “My favourites for this are red vein sorrel, parsley, basil, and fennel,” he says.