How much sun do tomato plants need?

Plus or minus four hours of sunshine for smaller tomatoes such as cherry Tomatoes. Larger size tomatoes need more sunshine, 8-10-12 hours. If you are not sure you have enough sunshine plant those tomatoes anyway.

Books say tomato plants need at least 4 hours of sunshine; on the other hand those tomato plants never read those books so plant anyway.

And remember, you are planting with ideal conditions, using great soil, fertilizing, properly watering, no trash talk, talking nice to the plants, etc. Most likely your plants will do fine and never know unless you try.

Plants need the sun or artificial light to manufacture their own food/energy. The tomato plants convert sunlight into food/energy and use that food/energy to make their fruit and sustain their own life. The more sunshine your tomatoes have, the more energy/food they will produce and the more fruit you will have.

The leaves are the food factories. Without enough extra sun, tomato plants may produce enough food/energy to stay alive but not enough extra food/energy to produce lots of tomatoes. Thus producing few or no tomatoes.

So pick a spot in the yard to plant your garden or locate your containers where you get at least 4-6 hours of sunshine, 8 hours and more is BEST. And if you don’t have that much sun—plant anyway and see how it goes. If you have less than 4-6 hours of sunshine, plant your tomatoes anyway.

Smaller tomatoes like cherry tomatoes need less sunshine than big beefsteak type tomatoes. Morning to early afternoon sunshine is better than midday to late afternoon sunshine.

But take whatever sunshine you can get. After 2 p.m. direct sunshine can be blistering hot and can damage tomatoes. When the after 2 p.m. sun is blistering hot make sure of two things:

  • Keep the roots moist even if you need to water twice daily
  • Cut some shade cloth strips about 3 foot wide, 6 foot tall and hang on the hot sun side of the cage. Leave the shade strip on 24/7.

Read more in the section about hot weather is the enemy of your tomatoes.

You are welcome to share this information with others. Are you a member of a garden club? Perhaps share this with your general membership to include those that could not attend the lecture.