@Notmyrealname85 imported plants have been shown to have less emissions than locally grown animal products.
I agree we should try to eat more locally grown food and we could base a lot of a plant based diet on it if we change our agricultural model so that only a small amount of imports would be needed. Oats, wheat, barley, potatoes, tomatoes, cucumber, carrots, kale, spinach, broccoli, cabbage, lettuce, apples, pears, plums, mushrooms, strawberries, blackberries, peas, various herbs, lentils, poppy seeds, sunflower seeds, rapeseed, garlic, onions, leeks, swedes, celery, spring greens, sugar, spring onions, parsnips, artichokes, squash, beetroot, watercress, rhubarb, Brussels sprouts, cauliflower, blueberries, French beans, runner beans, pumpkin, cherries, courgette, turnips, cranberries, chestnuts and sweet corn to name a few can all be grown in the U.K.
Bananas, coffee, tea, cocoa etc will need to come from abroad but most people are consuming these anyway whether they are plant based or on a standard diet so demand for them doesn’t need to increase.