Tomato tags call for full sun, which works great in places like the Midwest, Northeast or Pacific Northwest. In Southern California, the Deep South, Texas, and the Desert Southwest, though, where summer afternoons can get hot enough to fry eggs on the sidewalk, try to choose spots where tomatoes will receive morning sun, then filtered sun or light shade during the rest of the day. In areas in which there is no natural shade, create some yourself.
Key Takeaways:
- While most tomatoes like warmth, growing tomatoes in high temperatures requires choosing those varieties than can stand the heat and taking some extra steps to ensure they flourish.
- Tomatoes grown in very hot climes need extra mulching and extra hydration.
- Using row covers, or shade cover, to protect tomato plants from the day’s highest temperatures is critical to keeping tomatoes thriving in hot areas.
“Larger tomatoes generally take more time to ripen, so in hot climates, it is best to choose small to medium sized varieties. Also, if possible, plant cultivars that are disease and pest resistant.”
http://www.gardeningknowhow.com/edible/vegetables/tomato/hot-climate-tomatoes.htm