However, they can be started from seed if grown outdoors in late April or early May. Borage, basil and dill produce a large number of seeds and may start again the following year on a volunteer basis. Perennial and biennial herbs that can survive North Dakota winters include parsley, spearmint, peppermint, fennel and horseradish. Spearmint, peppermint and horseradish can withstand all but the most extreme of North Dakota winters. In fact, horseradish is so competitive that it can become an invasive pest if left unchecked. On the other hand, fennel and parsley should be protected as they may only survive a mild winter climate.
Perennials generally take a longer period of time to begin full production.
Herbs that are also classified as vegetables include garlic, peppers and mints. A listing of herbs that may be grown in North Dakota, and their uses and classification, is given in Table 1. Borage Annual Easily cultivated, good for making honey. Leaves and blooms have a subtle cucumber flavor when seeped in water. Dill Annual Seeds are used as flavor for dill pickles.