What Can I Plant With Jalapeno Peppers?
Some good jalapeno companion plants improve the flavor of the peppers. Basil, in particular, improves the flavor of all pepper varieties, jalapenos included, if it is planted nearby. Jalapeno companion plants that improve the overall health of the peppers include chamomile and marigolds, which release a chemical into the ground that drives away harmful nematodes and eelworms that prey upon pepper plants, among others.

There are plenty of other good jalapeno companion plants.
Some beneficial herbs include: Marjoram Chives Parsley Oregano Dill Coriander Garlic
Some good vegetables to plant near jalapeno peppers include: Carrots Asparagus Cucumbers Eggplants Pepper plants
Another good flower companion is nasturtium.

Non-Friendly Jalapeno Companion Plants
Certain plants detract in the flavor of the peppers, and also because both plants are big feeders of minerals in the ground and planting them near each other creates unnecessary competition.

Beans are not good jalapeno pepper companions and should not be planted near them. Peas should also be avoided. Anything in the brassica family are not good companions for jalapenos. These include: Cabbage Cauliflower Kale Kohlrabi Broccoli Brussels sprouts.

Some other plants that should be avoided are fennel and apricots.

Cutworms, aphids, and flea beetles are common pests of the pepper plant.

Jalapenos thrive in warm conditions and need temperatures between 65 and 80 F. (18-27 C.) to germinate. Temperature is critical, and unless it’s warm enough, pepper seeds won’t sprout and transplants won’t survive. It’s best to wait until at least two weeks after planting tomatoes to plant jalapeno peppers in the garden. In contrast, jalapeno pepper plants will not produce an abundance of fruit when the temperature is over 90 F. (32 C.)

Matures in 70 days.