While it is true that cucumbers and tomatoes can be planted together, you will need to keep in mind that there are a few things to remember when going about going this. The best thing you can do when trying to row cucumbers and tomatoes together is to plant them in a trellis. This way you will give them the best chance of flourishing.
You will also want to keep in mind that both tomatoes and cucumbers do very well in the summer months with full sunlight and lots of heat. It will be crucial to make sure that they receive the right amount of water and are planted in the appropriate soil in order to stimulate growth as much as possible.