Place your plants in an optimal location. Choose a location that gets adequate natural light (at least eight hours per day), is completely level and in the right kind of soil. Check the pH level of the soil and improve it with nutrients and minerals, such as lime and calcium, if necessary. Check with your local university extension office to find out what is the proper soil makeup for the vegetable crops you wish to grow.
Plant vegetables at the proper time to avoid frosts, and allow for growth during optimal temperatures. Check with your local university extension office to find out when the right time of year to begin planting is, and when you should start planning to harvest.
Keep track of the ambient temperature around the plants and consider adding mesh covering over them to protect against extreme temperature ranges. Covering the plants allows them to get needed sunlight and water, while protecting against the burning rays of the sun. It also allows the plants to retain warmth during cold overnight periods.
Maintain a high moisture content of the soil. Place plants with easy access to water and keep the soil moist without getting to the point of being muddy. Overly moist soil does not let the root systems of plants take hold, and will diminish production.
Be vigilant for pests and diseases that can decrease output. Use commercial or homemade pesticides to keep plant borers and flying insects away from your plants. Watch for telltale signs of diseases, such as leaf rot or leaf blight, which will manifest as discolorations on the vegetables' leaves. Contact your agricultural supplier for information on how to treat plant diseases. Keep plants as weed-free as possible -- weeds compete with the plant for nutrients.
Make good use of the planting space you have, even in limited areas. Consider planting early harvest vegetables, such as lettuce and radishes next to late harvest vegetables, such as potatoes and squash. Grow as many crops as you can vertically using trellises and stakes.
Plant cover crops, such as soybeans, clover or alfalfa once you have harvested your vegetables. This will help maintain the nutrient level of the soil, and you can also possibly sell your cover crops to local farmers as feed for extra profit, or use yourself.