The Capitulary lists over 70 species of flowers, herbs and vegetables and 16 kinds of fruit and nuts: it represents an excellent synoptic account of vegetables, fruits, and herbs of the day that would have been widely copied and passed between the castles and monasteries of Europe.
70. It is our wish that they shall have in their gardens all kinds of plants: lily, roses, fenugreek, costmary, sage, rue, southernwood, cucumbers, pumpkins, gourds, kidney-bean, cumin, rosemary, caraway, chick-pea, squill, gladiolus, tarragon, anise, colocynth, chicory, ammi, sesili, lettuces, spider’s foot, rocket salad, garden cress, burdock, penny-royal, hemlock, parsley, celery, lovage, juniper, dill, sweet fennel, endive, dittany, white mustard, summer savory, water mint, garden mint, wild mint, tansy, catnip, centaury, garden poppy, beets, hazelwort, marshmallows, mallows, carrots, parsnip, orach, spinach, kohlrabi, cabbages, onions, chives, leeks, radishes, shallots, cibols, garlic, madder, teazles, broad beans, peas, coriander, chervil, capers, clary. And the gardener shall have house-leeks growing on his house. As for trees, it is our wish that they shall have various kinds of apple, pear, plum, sorb, medlar, chestnut and peach; quince, hazel, almond, mulberry, laurel, pine, fig, nut and cherry trees of various kinds. The names of apples are: gozmaringa, geroldinga, crevedella, spirauca; there are sweet ones, bitter ones, those that keep well, those that are to be eaten straightaway, and early ones. Of pears they are to have three or four kinds, those that keep well, sweet ones, cooking pears and the late-ripening one 
While some Roman-introduced fruits and vegetables may have lapsed into disuse others were now finding their way out of the gardens and into the countryside including Fennel Foeniculum vulgare, Ground-elder Aegopodium podagraria, and Wormwood Artemisia absinthium. Sweet and sour cherries survived neglect and Roman introductions like dill, lettuce, kale, radish and beet were all now cultivated.
A list of 200 widespread plants was compiled by Aelfric of Eynsham’s student Aelfric Bata in 995 as a Colloquy or Latin primer, the Roman introductions possibly indicated by the similarity of the Anglo-Saxon words to their Latin names e.g. Petroselinum-Petersilie-Parsley, Ruta-Rude-Rue. Practical use took precedence over beauty and this is reflected in their Anglo-Saxon names. Which from the 10-12th centuries were given Christian equivalents.
Rosemary int. to England with Queen Philippa in 1340.
Wallflowers, stocks, hollyhock in 14th century probably with Queen Eleanor of Castile c. 1255.
Carnations enjoyed a cult status being vary popular in Valencia in 1460 and thought to have arrived from Persia via Turkey and Italy.
Orchards were no doubt planted in eh Early Middle Age fruit trees, some introduced by the Romans, were grown by the Anglo-Saxons. Benedictine monks before the Norman Conquest were expected to maintain orchards although these might not have been confined to fruit trees.