There's a book called Carrots Love Tomatoes that's all about companion planting. I have been planting carrots with tomatoes in pots for a few seasons, and tried in the ground this year. But there was too much watering (carrot seedlings are floppy and wimpy) and not enough sun. So sharing the box with with my tomatoes are the zucchini, which grew like gangbusters, and some Armenian cucumber plants that were slow to take off. First the seedlings were eaten by birds, bugs, I dunno but they were topped - basically the stem was chopped off and the plant didn't have the energy to regrow - so I planted more seeds. The second round of seedlings didn't get decapitated, but they were soon shaded by the other plants. So I didn't have high expectations. But lately, the cucumbers have more than embraced their neighbors. The cucumbers are weaving their way through the tomato plants! See the yellow flower and the tendrils? And I found my first fruit today. The Armenian cucumbers have a soft skin that doesn't need to be peeled and have a pretty shape when cut. This is the seed pack I bought.