Return to the Growing Tomatoes Forum | Post a Follow-Up

Can a tomato plant get too much light?

Posted by growneat (My Page) on
Mon, Jul 14, 14 at 14:21

I have read where in most locations during the time of the year when the sun is nearly overhead that tomato plants get far more sunlight than they need or actually use, in some places using only around 50% of the light available. Does excess light do any damage to the plants or tomatoes other than the effect of the light on temperature, ie heating the tomato and plant up such as sunburn?

Follow-Up Postings:

RE: Can a tomato plant get too much light?

  • Posted by digdirt 6b-7a North AR (My Page) on
    Mon, Jul 14, 14 at 18:42

Damage from light? No. From heat? Yes.


RE: Can a tomato plant get too much light?

Like any plant, tomato can benefit from sun (direct exposure) to some limit. In the midst of summer with 15 hours of daylight, tomatoes do not need 15 hours of sun. Logically there must be an optimum amount that it needs. When they say "full sun" that does not imply 12 to 15 hours of direct light. Six hours is often considered full sun (Lower limit) Perhaps 8 hours should be enough.

One thing to remember is that tomato can get quite a lot of light indirectly for its photosynthesis need. It has bee said that light intensity in a day with overcast skies is almost equal to what plants get under fluorescent light. Or very close to it.

With direct sun also comes heat energy. Again, plants need certain amount of heat. That can be found in indirect light exposure too. In general most plants would rather have temperatures in 70 to 86F.

I am growing tomatoes with 4.5 to 5.5 hours of direct sun. I am doing ok but I think 7-8 hours would have been ideal even in our cool PNW.

That is my take according to my own experience. I have also gardened in GA with about 6-7 hours direct sun. In the dog days of July and August that seemed to be more than necessary.

 o Post a Follow-Up

Please Note: Only registered members are able to post messages to this forum.

    If you are a member, please log in.

    If you aren't yet a member, join now!

Return to the Growing Tomatoes Forum

Information about Posting

  • You must be logged in to post a message. Once you are logged in, a posting window will appear at the bottom of the messages. If you are not a member, please register for an account.
  • Posting is a two-step process. Once you have composed your message, you will be taken to the preview page. You will then have a chance to review your post, make changes and upload photos.
  • After posting your message, you may need to refresh the forum page in order to see it.
  • Before posting copyrighted material, please read about Copyright and Fair Use.
  • We have a strict no-advertising policy!
  • If you would like to practice posting or uploading photos, please visit our Test forum.
  • If you need assistance, please Contact Us and we will be happy to help.

Learn more about in-text links on this page here