Cucumbers are considered compatible with tomatoes. The two plants are companion plants, mutually beneficial to each other. Both tomatoes and cucumbers dislike growing near potatoes.Click to see full answer. Hereof, what should not be planted with tomatoes? Bad Companions for Tomatoes Cabbage (Brassica) family: All relatives of cabbage stunt the growth of tomato plants (including broccoli, Brussels sprouts, cabbage, collards, cauliflower, kale, kohlrabi, rutabaga, and turnip). Corn: The corn earworm is the same as the tomato fruitworm. (Also known as the cotton bollworm.)Likewise, what can I plant next to cucumbers? Cucumbers To repel aphids and beetles, plant marigolds and nasturtiums among your cucumbers. Beans, celery, corn, lettuce, dill, peas, and radishes are also good companion plants. Keep cucumbers away from: Aromatic herbs such as sage which will stunt the growth of cucumbers. Herein, what vegetables should not be planted next to each other? Bad Plant Combinations Beans, beets, cabbage, carrots, cauliflower, corn, cucumbers and strawberries make good neighbors — as long as you plant the onions, garlic, leeks and shallots elsewhere. Peppers do well with carrots, eggplant, onions, parsley and tomatoes, but do not plant kohlrabi anywhere near them.Can you plant watermelon next to cucumbers?Different types of cucumbers can cross, but even then it only affects the next generation via the seeds. Likewise melons; but not watermelon, that’s a whole different plant. So the first answer is ‘Yes’, yes you can plant them together.