General remarks:The use of herbs and spices in Russia, Poland, Bohemia, Hungary and parts of Germany during the medieval and Renaissance periods is well attested, but there is not a great deal of information translated into English on the subject. Herein I have tried to collect the information that exists in the books I have access to. Many cultures of Eastern Europe experienced dramatic culture importation late in period: the Hungarian Turkish invasion, the Russian Mongol influence, and in Poland/Lithuania, the Italian influences of Bona Sforza. (In Poland, soup greens are still known as 'italian vegetables'.) Bohemians, Hungarians and Poles all had access to the famous health handbook by Platina, as well as Dioscorides De Materia Medica (which Zevin says was also known in Russia). Hungarians in particular have a wide variety of influences on their cuisine and accessibility of herbs/spices because of the waves of Pechneg, Cuman and other Asian migrants, as well as the original Magyar influences. The more westerly parts of eastern Europe were probably heavily influenced by their western neighbors; Russia was influenced by Constantinople and by the Byzantine Empire as a whole. There is a theory that after the fall of Rome and before the re-opening of the Mediterranean spice/silk route, the trade caravans with their spices traveled through Russia, which might have made spices more available in Russia before 1300.
Though Russian healers like to claim a long-standing, continuously vital tradition of herbal healing, the author of the Domostroi strongly condemns the use of herbs in healing: ". . . any abomination detested by god . . .are included anyone who tries to defeat death with sorcery, herbs, roots, or grasses . . ."; from the sound of the Russian priest's denunciations, the Russian herbal healers of the 16th century probably had as hard a time of it as Western European herbal healers are supposed to have had. The anonymous author does mention 'beneficial herbs' to be used in brewing, but gives no details; only a few spices and the ever present hemp, hops and poppy seed show up in the Domostroi.
By the late 16th century, botanical gardens were well-established in Eastern Europe, especially in Germany, and botanical faculties were established at Universities. Publications such as Fuchs' Great Herbal and Falimirz's Herbarium tend to blur the line between what plants were used and which were merely curiousities studied on the academic level. Capsicum (hot pepper) is one example.
One special use of herbs that deserves mention in Eastern Europe is sweat/steam/vapor baths. Hildegarde of Bingen suggests a number of herbs to be used either in water baths or in vapor baths (in Germany). Mikkel Aaland's article on the Russian Bania quotes a period source that suggests herbs may have been used in Russian steam baths: Adamus Olearius, in his Persian Travel Tales of the early 1600s, says " The Germans who dwell in Muscovy and Livonia are very nice in their Stoves; they strew Pine Leaves powder'd, and all sorts of Herbs and Flowers upon the Floor; which, together with the Lye make a very agreeable Scent."