How Many Hours of Sunlight Does a Vegetable Garden Need?

Tomatoes and cucumbers need more sun than leafy greens.

Most garden crops need a lot of sun to produce well. Plants that don't get enough sun tend to be spindly, thin-leaved or poor-fruiting. On average, most vegetable gardens need at least six hours of direct sun daily, but this can vary depending on the individual vegetables in the garden. Choose bright, sunny areas whenever possible and plant according to the amount of light available.

Leafy Greens

Leafy green vegetables, such as spinach, lettuce, chard and collards, do best in plenty of sun but should not get too much heat. Plant greens in full sun when growing them during the spring, but provide a little shade in the summer to prevent a bitter flavor. Summer greens exposed to heat and sun may also tend to bolt, or put up flowers, reducing their useful growing season.

Fruiting Plants

Fruiting plants, such as peppers, tomatoes, eggplant and squash, need as much sun as possible. Ohio State University recommends providing at least six to eight hours of sunlight per day for the best results. Most fruiting plants do better the more sun they receive. However, some fruits can develop a problem called sunscald when exposed to very hot sun during the warmest days of summer. This produces hard, light-colored patches on vegetables and encourages rot. In areas where sunscald is a danger, plant vegetables so they receive shade during the hottest part of the day.

Roots

Root vegetables tend to require significant sun as well, though not as much as many hot weather fruiting plants. The Portland Nursery and Garden Center suggests that beets and other tubers should get at least six hours of direct sun for proper root development. These vegetables do best in as much sun as possible, but can tolerate partial shade better than tomatoes and similar fruiting plants.

Low Light

Not all garden plots receive ideal amounts of light. A shady garden won't do as well as a brightly lit one, but can still produce good quality vegetables. Choose cool season vegetables such as radishes, cabbage and roots. Gardens which receive less sun than appropriate for growing good root vegetables may still produce greens from the same plants. According to the Portland Nursery and Garden Center, four hours of sun will grow turnip greens, beet greens and radish greens. Gardeners may also use reflectors and similar devices to increase the amount of sun available, but should take care to avoid burning the vegetables with reflected heat.

References

• Iowa State University: Where to Put Your Vegetable Garden
• Virginia Tech: Leafy Green Vegetable
• Clemson Cooperative Extension: Tomato
• Portland Nursery and Garden Center: Beets
• Ohio State University: Growing Cucumbers, Peppers, Squash and Tomatoes in Containers
• University of Minnesota: Gardening in the Shade