The following Western plants are mentioned in the 14th century YSZY, 28 of them in all. Some, like the grain-of paradise, cardamoms from Africa, were exotic imports:
Almond
Barley
Basil
Chickpeas
Citron
Coriander
Cucumber
Fennel
Fenugreek
Garlic
Grains-of-paradise
Grape
Lettuce
Onions, western ball
Pistachio
Pomegranate
Poppy seeds
Rape-turnip
Safflower
Saffron
Sesame
Shallots
Spinach
Sugar beet
Swiss chard
Vetch
Watermelon
Wheat, bread and durum (unmistakably described and differentiated)
By contrast with this list, the Huihui Yaofang includes 67 Western plants used medicinally. These were traded into China by land along the Silk Roads but most probably came by sea by the time that the Huihui Yaofang was compiled.
Agaricus campestris, common field mushroom (possibly native to China too)
Allium cepa, ball onion
Allium sativum, garlic
Althaea rosea and/or officinalis, mallow, hollyhock
Anethum graveolens, dill
Apium graveolens, celery
Asparagus officinalis, but the Chinese asparagus that was probably used as a substitute is not a normal food, though edible.
Beta vulgaris, beet (chard or something similar is implied)
Borago officinalis, borage
Brassica alba (possibly also B. nigra), mustard
B. campestris, Chinese mustard greens, Chinese cabbage
B. oleracea, western cabbage, broccoli
Capparis spinosa (but probably not the substitutes they would probably use), caper
Carum copticum, black caraway
Ceratonia siliqua, carob
Cheiranthus cheiri (marginally a food), wallflower
Cichorium endivia, chicory
Cordia myxa (marginally a food; fruit edible but nobody in cent or E Asia eats it except for medicine), sebesten
Coriandrum sativum, coriander
Cornus mas, dogwood, cornelian cherry
Crocus sativus, saffron
Cucumis melo, melon (possibly native to China also)
Cydonia oblonga, quince
Cyperus rotundus, grassnut
Daucus carota, carrot (Afghanistan/Iran)
Eruca sativa, rocket, arugula
Ferula asafoetida, asafoetida
Ficus carica, fig
Foeniculum vulgare, fennel
Fraxinus excelsior, manna ash
Hordeum vulgare, barley
Hyssopus officinalis, hyssop
Laurus nobilis, laurel
Lavandula stoechas (possibly other spp.), lavender
Lepidium latifolium, cress, peppergrass
L. sativum, cress, peppergrass
Linum usitatissimum, flaxseed
Lupinus albus (and/or L. termus), lupine
Malus communis, apple (native to Kazakhstan)
Marrubium vulgare, horehound
Melilotus officinalis, sweet clover
Melissa officinalis, lemon balm
M. haplocalyx, mint
M. pulegium, pennyroyal
Nigella sativa, love-in-a-mist, black caraway
Ocimum basilicum (and probably other spp.), basil
Olea europea, olive
Origanum spp., oregano
Papaver somniferum, opium poppy
Petroselinum hortense, parsley
Phoenix dactylifera, date
Pimpinella anisum, anise
Prunus amygdalus, almond
P. armeniaca, peach
P. domestica, plum (but Chinese P. salicina was probably actually used)
P. mahaleb, mahleb cherry
Punica granatum, pomegranate
Rhus coriaria, sumac
Rosmarinus officinalis, rosemary
Salsola kali, Russian thistle
Sesamum indicum, sesame
Solanum melongena, eggplant
Thymus spp. incl. serpyllum, thyme
Trigonella foenum-graecum, fenugreek
Triticum spelta, spelt (wheat)
Vicia ervilia, vetch
Vitis vinifera, grape