If your summer gardening plans include growing a few vegetables in containers, peppers should be on your planting list. When the right varieties are given attentive care, peppers can grow better in pots than in a garden, especially in cool or windy climates. Early in the season, peppers grown in containers enjoy warmer roots than they might have deep in the ground, and later on when the plants become loaded with fruit, moving them to a protected spot will keep the brittle branches from breaking off.
Not all varieties are a good fit for containers. In my experience and that of others like the Pennsylvania Master Gardeners, small-fruited peppers with a bushy, branching growth habit are the best choices for pots. That said, one of my reasons for growing peppers in containers is to make sure I have them close to the kitchen door for quick picking, so I veer toward little sweet peppers and moderately hot jalapenos.
If I were limited to growing all of my peppers in containers, I would favor ‘Redskin’ or ‘Mohawk’ for sweet peppers, and perhaps ‘Apache’ for more spice. Cool trivia: all three of these excellent container varieties were bred in the UK.
Potting Up Peppers
Whether you start with purchased seedlings or sow your own, you will quickly discover that young pepper plants benefit from “potting up” to the next size container as often as every two weeks. Use a good quality potting mix and avoid disturbing the roots at each repotting, in which the new container should provide about two inches of new growing space on all sides. By the time my peppers are in their permanent pots, I have usually repotted them four times. Big pepper plants often need daily watering in hot weather, so I like to use lightweight, water-retentive plastic pots when growing peppers in containers.
Depending on your climate, your peppers may be fine growing on a patio table, but in hot weather the plants benefit from having their roots shaded from intense sun. This is easy to do by placing the pots in a shallow crate or planter, or even a cardboard box. If left unshaded, dark-colored pots in particular are prone to overheating on sunny days.
Feeding and Watering Container Peppers
Peppers may have few insect pests, but they have an above-average need for thoughtful feeding and watering. First let’s talk water, because peppers grown in containers must never be allowed to dry out, and grow best with constant light moisture. How often you must water depends on the weather, but you can easily tell how dry the pots are by tipping them slightly to judge their weight. Very light pots are dangerously dry. Should a big potted pepper dry out to the point of wilting, you will need to water it several times to put things right.
The easiest way to feed peppers growing in containers is to use a water-soluble liquid plant food every week or so, when the plants are well hydrated and not under stress. Underfed plants have pale green leaves and show little new growth, while happily fed ones get busy producing lots of flowers and fruits.
I often alternate homemade liquid fertilizers with various commercial products, which makes feeding my peppers as much intuition as science. If I were to buy a fertilizer especially for potted peppers, it would serve as a good source of all three major nutrients, plus calcium and magnesium to prevent nutritional stress during fruit set. Most organic fertilizers developed for tomatoes will fill the bill, but do read the label so you will know what your peppers are getting.
Pepper varieties with a spreading growth habit like ‘Redskin’ need no staking, but upright jalapenos benefit from being tethered to a secure stake – or maybe two or three. Grow-through plant hoops are great for large plants, or you can make a wire cage to fit the pot. In addition to staking, you can move container-grown peppers to a place sheltered from wind and strong sun when they load up with fruit. This is the best way to be sure that your beautiful potted peppers make it into the kitchen.