Plants that form their seeds inside of the edible part are technically fruits, according to botanical classification. The ones we call vegetables – tomatoes, peppers, eggplant, cucumbers and squash – all grow best in hot weather.
They require a minimum of 6 to 8 hours of sun a day and moist, rich, fertile soil, with plenty of regular rainfall. Plant them together in pots or group pots of them together. A 5-gallon container is adequate for one tomato plant. A half whiskey barrel is large enough to support three plants each of tomato, pepper or eggplant.
Growing best in the cool weather of early to mid spring, leafy vegetables require similar cultivation practices. Lettuce, spinach, arugula, kale, mustard greens and other salad or cooking greens prefer well-drained soil of average fertility.
These crops can grow well on a bit less sun than hot-weather-loving vegetables, doing well on just 6 hours of sun a day. Broadcast seeds of leafy vegetables over the entire surface of the growing container.
Harvest baby greens, beginning when they are a few inches tall, allowing the remaining plants to grow larger before harvesting. Grow leafy vegetables in containers 8 inches in diameter or larger.
Most root vegetables are planted in the cool weather of early spring, but grow throughout the summer for harvest later in the season. Plant carrots, onions, beets or rutabagas in the same container, as they all require similar growing conditions. Give them a minimum of 7 to 8 hours of direct sun a day.
Root crops grow best in soil of average to low fertility, but the soil must be loose, friable and free of rocks and stones to a depth of about 6 inches. Use your deepest containers for growing root crops, to give them enough room to mature.
Space root vegetables approximately the same distance apart in all directions. Plant their seeds the minimum distance apart, as recommended on the seed packet. Use at least 10- to 12-inch diameter pots for root crops.
Tips for Successful Container Gardening
Ensure the containers you use have drainage holes in the bottoms, to allow excess water or rainfall to drain away. Standing, undrained water can cause the roots to suffocate.
Some plants, especially those that receive sun most of the day, may need to be watered twice a day during the hottest days of summer. Check container gardens daily, especially during the hottest part of summer, when they may need watering every day.
Fertilize container-grown plants with a water-soluble fertilizer. Apply the solution by watering the soil in the pots with it, immediately after a thorough watering with plain water. Moist soil helps plants better absorb nutrients.