Gather your pots and planting material
Grow pepper plants indoors in as much sun as you can manage, watering as need be. And in the meantime, gather your containers—sturdy plastic, pretty terracotta or wood. Size matters: containers should be at least 30 centimetres in diameter and about the same depth. Bigger is even better (within reason). Nursery pots left over from shrubs or trees can be recycled for peppers; and it’s best to grow just one plant per pot.
The growing medium is as important as pot size: soil must be light-textured, porous and water retentive. A bagged blend is convenient, and an organic mix formulated for container vegetables is best. But we have grown peppers for years in a homemade mix of two parts sandy garden soil, one part sifted compost and one part peat moss, coir and/or vermiculite. A handful of bone meal in each pot boosts phosphorous, a nutrient that helps with fruiting. Where the natural garden soil runs to clay, start with bagged soil, since clay can “smother” roots. To facilitate watering, leave at least 3 centimetres between the soil and the container’s rim.
Caring for your plants
Pepper plants are very prone to frost damage, and even a chilly night or two will cause flowers to drop. Wait until all danger of frost is past, and night temperatures are consistently above 7°C before transferring young plants to pots for the summer and setting them outdoors. A few days of gradual exposure to the outside elements lessens the shock.
Sitting in the hot sun, containers can overheat and dry out quickly. For cooler roots and steady growth, group pots close together and check water needs daily. Peppers tell you when they’re thirsty by a slight wilting of leaves. That does no harm, but it’s better to act before the fact. To prevent mildew, water soil rather than plants. Pour on a monthly dose of liquid fertilizer formulated for vegetables, or insert organic fertilizer spikes into the soil according to directions at planting time.
A bonus? Well-grown container peppers, with their shiny fruit dangling against dark green leaves, are as decorative as any other potted plant on your deck, porch or patio.
There’s no such thing as a green pepper—or more precisely, a pepper that stays green. All peppers start out some shade of green—either dark, light or yellowish—and gradually turn red, yellow, orange or even purple as they mature and sweeten. A green pepper, like a green tomato, is simply unripe.