The last two years my cucumber plants became diceased and died.
The leaves became shrivelled and brown.
Do other gardeners grow these plants together?
I don't know about harming each other, but they do need differing growing conditions. Many people reckon they are very hard to grow together. I'm not sure about that, I just think all cucumber plants hate me!
Don't know about the cucumbers, but have been advised to grow basil and tomatoes together. Not only do they taste good together, but the basil plants will become stressed and show it before the tomatoes do. Not tried it yet, but am going to in my little plastic greenhouse and tomato hanging baskets this year. If it works out I will have some lovely ingredients for pasta sauce, if not I will know for next year!
Cucumbers prefer more humidity than tomatoes. If you can separate them into different compartments in a green house fine, but if not you are always having to compromise. If the tomatoes get the humidity the cucumbers love, they are more likely to get fungal infections such as blight. My mum does really well with cucumbers in a partitioned off area that gets less light and ventilation. The main greenhouse has tomatoes in and more light and plenty of ventilation. My greenhouse has only one compartment and I never do well with cucumbers indoors. I've started growing marketmore ridge cucumbers outdoors.