How Much Sun Minimally?

GoDawgs · May 3, 2020

I've read where tomatoes only need about 6 hours of sun to produce and I need some input as to what real life experience says. After last year's fiasco of trying half of the tomatoes in buckets in full, all day Georgia sun where they got baked and broiled and were really unhappy, this year I changed that planting site to one higher up in the garden where they'll get some afternoon shade. Now I'm afraid that perhaps it's too shady.

It might be that the sunlight right now might be less than it will be as spring turns to summer and the sun moves around. We'll see. The problem is that I did no real prior sun study and relied on memory. I checked all my photos from last year but I can't get a sunlight handle on that corner of the garden because I didn't take many photos of it.

So how many hours of direct sunlight do the tomatoes really need to "be fruitful and multiply"? I can't change the location now as everywhere else in the garden is occupied and in full sun. So am I up the creek without the paddle and ruined it all or is there some hope? Fortunately the other half of the tomatoes are in buckets in a good situation up near the house but these in the garden are eleven new-to-me varieties.

zipcode · May 4, 2020

They will produce with less, but to get a good crop something like 5 hours is indeed kinda required. Indirect light is also more important than it seems. For example a tomato under a tree that gets 5 hours of sun (when it's sunny) will be quite unhappy, compared to one against a wall where it gets bounced off light all day and also on cloudy days.
I think it should be fine, morning sun is great, keeps disease away and statistically, it's more sunny in the morning than in the afternoon.

slugworth · May 4, 2020

One spot last year only got the sun in the morning til noon,then was in the shade.
Some tomatoes never got ripe even on the plants for months.
Another spot got 3/4 sun during the day,performance really dropped off once September rolled around.

JRinPA · May 4, 2020

Our "garden" - the original one in the backyard - for years only received direct light from maybe 10 am to 4 June (EDT). Before 10am, deep shade from Arbor Vitae walls. It was enough. The tomatoes grew well, but the leaves stay wet in the morning. It gets some more now due to trees being cut, but I have only grown tomatoes there once in the last 4 years.

I thought perhaps moving tomatoes to a sunnier location would help. It probably has helped some for production, but they get a more sunscald with the greater exposure and nearly full sun at the comm garden. They still get the same foliage diseases, even with single or double stem, black mulch, and trimming 2 ft up. Honestly, I think they die earlier in the year simply due to less overall vigor from the greatly reduced foliage. And more exposure. Some of the tomatoes, like OR117, perform very poorly over there in cages. I think they have longish internode length to start with. The ones that did fruit were mostly mush from the heat. I have the most success there with florida weave and close spacing for shade and lots early production, but those plants are toast by September.

Probably the worse production I have had locally on tomatoes that had enough water were tomatoes grown near the 40' tall arbor vitae row that walled off the SE exposure. They grew distinctly more skinny and long, farther between leaves, than comparable plants elsewhere. It's like they were looking for the sun for half of each day. They had a good strong overhead sun in June from 12P to 5 P. The fruit set was just sparse though, and the tomatoes particularly small and bland. That same plot, with the arbor vitae cut down and ample morning sun, was wonderful for tomatoes. Last year it was superb for romani peppers.

I can grow right along the back of the house, about as well as any place. That is a North East exposure. In June the tomatoes get direct sun from about 7-8am (when it clears the neighbors arbor vitae wall 30-40 yards away) to 3pm when it becomes solid shade from our house. That is the hottest part of the day here, 3-6 pm daylight time. I think the shade at that time really helps.

Ideally, for a tomato/pepper/eggplant plot, I would want full sun from daybreak to about 3 pm, then partial shade. I would consider that the garden lottery win, but I have never lucked into that. It might not be any better, but I'd love to try it.

Koala Doug · May 4, 2020

I can only muster an average of about three-and-a-half hours of direct sunlight per day - up to five hours before the leaves fill in (mid-May) and down to two hours by the first of October. Too many large, mature trees... it is just the burden I must bear for living in this particular neighborhood. It also means I can't plant in-ground and have to use containers that sit on my concrete driveway (the only part of the property that gets any direct rays).

The lack of direct sunlight makes the plants stretch and obviously would decrease the yield - as well as the size of the fruit - but I can still harvest a good amount of yummy tomatoes. I had more trouble before I switched to Texas Tomato Food - that stuff really made a significant difference.

Everybody told me I couldn't grow tomatoes here, but I certainly can even with barely any direct sunlight. If the plants have the nutrients that they seek, and in the amounts that they want, then you'll still be able to get a decent harvest.

I think Craig LeHoullier also used to have limited sunlight at his previous property in Raleigh. Maybe he can chime-in here on this subject.

**nctomatoman** · May 4, 2020

Hey Koala and all = thanks for highlighting this thread to me. In my driveway I got 5-6 hours of direct sun, but also grew on concrete, and we had 70 days of 90 degrees or above - so my yields were quite excellent (25 lbs of fruit per indeterminate plant in a straw bale).

I like to advise gardeners that in very low light - 2-3 hours of direct sun - stick with smaller fruited varieties (cherry to golf ball sized). All day full sun will grow all varieties well IF sufficient water and food is supplied. Temps at 90 and above, esp in high humidity, will lead to blossom drop on the heirloom beefsteak types. Allowing plants to visibly wilt in the hot parts of the day cause plant stress, which will result in blossom end rot.

GoDawgs · May 6, 2020

Many thanks for all of the replies! I need to set a reminder timer every day to go check the sun/shade status at various times. It appears that the time stamp feature on my camera is out of whack. I had been relying on that as I don't have a watch anymore and don't carry my phone in the garden.

slugworth · May 6, 2020

There are digital light meters that actually record the data.
I got the HS1010 meter at goodwill last year but never played with it.
1-200,000 lux resolution.
I could probably do a survey over the course of a day to get data for
different parts of the yard.
Time for a new camera lithium battery maybe.

GoDawgs · May 6, 2020

It's just a relatively inexpensive Canon Power Shot A1300 I've had for ages. I wanted it because it was one of the only ones out there that runs on two AA alkalines (didn't want lithium) and it has the old fashioned view finder in addition to the display. Sometimes with the sun at my back I can't see squat on the display.

The zoom doesn't work right as it hangs up and then I have to give it a light tap to get it to retract so I don't use it. Maybe a grain of sand in there. Now the time stamp thing. New batteries, too. Oh well, it takes the pics I want and the iPhoto enhances them.

slugworth · May 6, 2020

My powershot A410 has a separate battery for the clock/calendar
CR1220 which I didn't have handy so I used a CR1216
same diameter but thinner.
In a plastic holder bottom left corner of the camera.
One of these days I will get a proper battery.

b54red · May 6, 2020

I have an odd shaped garden that is almost a triangle and the lower end of the triangle gets shade starting from between 2 and 4 every day depending upon the time of the year. I usually reserve that lower portion for later planted bell peppers which appreciate the shade in late summer and early fall but they don't produce as well and they tend to be leggy as well. When I grow tomatoes down in that portion of the garden my results are always disappointing with smaller fruit and actually less tasty tomatoes. The vines tend to be much thinner and fruit set is not as good as in more sunny locations. I wish I could convince my neighbors to take down some trees so I could go back to the sunny garden I had 40 years ago when the trees were very small.

Bill

GrowingCoastal · May 7, 2020

Quote:

Originally Posted by nctomatoman

Allowing plants to visibly wilt in the hot parts of the day cause plant stress, which will result in blossom end rot.

Also a precursor to powdery mildew on my tomato plants here.

I have had both Paul Robeson and Stump of the World get BER with only regular watering. I need to give them more water than any other varieties in order not to get BER on their fruit.

slugworth · May 7, 2020

I've had tomato plants with both plum shaped and round tomatoes (like anna russian)
The plum got BER,the round ones were fine same age same exact plant.

KathyDC · May 26, 2020

I plant in my back yard which has western and southern exposure, the sun rises and the house will shade the back yard until about 9am when it's up high enough that the back yard starts getting sun. They'll get full sun until about 3pm when the sun starts dipping down and unfortunately then all my neighbor's rampant derelict foliage starts getting in the way (in past years, I would get full sun until about 4pm, but unfortunately they don't take care of their property so another tree has been allowed to grow at the corner). After about 3pm I get dappled light/shade.

This is the first year the sun will be stopping quite so soon, typically I have had until closer to 4pm. So I'll see how they do, but I anticipate they will be OK.

May 3, 2020	#1
GoDawgs Tomatovillian™ Join Date: Feb 2018 Location: Augusta area, Georgia, 8a/7b Posts: 1,685	How Much Sun Minimally? I've read where tomatoes only need about 6 hours of sun to produce and I need some input as to what real life experience says. After last year's fiasco of trying half of the tomatoes in buckets in full, all day Georgia sun where they got baked and broiled and were really unhappy, this year I changed that planting site to one higher up in the garden where they'll get some afternoon shade. Now I'm afraid that perhaps it's too shady. It might be that the sunlight right now might be less than it will be as spring turns to summer and the sun moves around. We'll see. The problem is that I did no real prior sun study and relied on memory. I checked all my photos from last year but I can't get a sunlight handle on that corner of the garden because I didn't take many photos of it. So how many hours of direct sunlight do the tomatoes really need to "be fruitful and multiply"? I can't change the location now as everywhere else in the garden is occupied and in full sun. So am I up the creek without the paddle and ruined it all or is there some hope? Fortunately the other half of the tomatoes are in buckets in a good situation up near the house but these in the garden are eleven new-to-me varieties.

May 4, 2020	#6
nctomatoman Tomatoville® Moderator Join Date: Jan 2006 Location: Hendersonville, NC zone 7 Posts: 10,385	Hey Koala and all = thanks for highlighting this thread to me. In my driveway I got 5-6 hours of direct sun, but also grew on concrete, and we had 70 days of 90 degrees or above - so my yields were quite excellent (25 lbs of fruit per indeterminate plant in a straw bale). I like to advise gardeners that in very low light - 2-3 hours of direct sun - stick with smaller fruited varieties (cherry to golf ball sized). All day full sun will grow all varieties well IF sufficient water and food is supplied. Temps at 90 and above, esp in high humidity, will lead to blossom drop on the heirloom beefsteak types. Allowing plants to visibly wilt in the hot parts of the day cause plant stress, which will result in blossom end rot. __________________ Craig

May 4, 2020	#2
zipcode Tomatovillian™ Join Date: Jun 2010 Location: Romania/Germany , z 4-6 Posts: 1,582	They will produce with less, but to get a good crop something like 5 hours is indeed kinda required. Indirect light is also more important than it seems. For example a tomato under a tree that gets 5 hours of sun (when it's sunny) will be quite unhappy, compared to one against a wall where it gets bounced off light all day and also on cloudy days. I think it should be fine, morning sun is great, keeps disease away and statistically, it's more sunny in the morning than in the afternoon.

May 4, 2020	#3
slugworth Tomatovillian™ Join Date: Oct 2014 Location: connecticut,usa Posts: 1,152	One spot last year only got the sun in the morning til noon,then was in the shade. Some tomatoes never got ripe even on the plants for months. Another spot got 3/4 sun during the day,performance really dropped off once September rolled around.

May 4, 2020	#4
JRinPA Tomatovillian™ Join Date: Jul 2013 Location: SE PA Posts: 972	Our "garden" - the original one in the backyard - for years only received direct light from maybe 10 am to 4 June (EDT). Before 10am, deep shade from Arbor Vitae walls. It was enough. The tomatoes grew well, but the leaves stay wet in the morning. It gets some more now due to trees being cut, but I have only grown tomatoes there once in the last 4 years. I thought perhaps moving tomatoes to a sunnier location would help. It probably has helped some for production, but they get a more sunscald with the greater exposure and nearly full sun at the comm garden. They still get the same foliage diseases, even with single or double stem, black mulch, and trimming 2 ft up. Honestly, I think they die earlier in the year simply due to less overall vigor from the greatly reduced foliage. And more exposure. Some of the tomatoes, like OR117, perform very poorly over there in cages. I think they have longish internode length to start with. The ones that did fruit were mostly mush from the heat. I have the most success there with florida weave and close spacing for shade and lots early production, but those plants are toast by September. Probably the worse production I have had locally on tomatoes that had enough water were tomatoes grown near the 40' tall arbor vitae row that walled off the SE exposure. They grew distinctly more skinny and long, farther between leaves, than comparable plants elsewhere. It's like they were looking for the sun for half of each day. They had a good strong overhead sun in June from 12P to 5 P. The fruit set was just sparse though, and the tomatoes particularly small and bland. That same plot, with the arbor vitae cut down and ample morning sun, was wonderful for tomatoes. Last year it was superb for romani peppers. I can grow right along the back of the house, about as well as any place. That is a North East exposure. In June the tomatoes get direct sun from about 7-8am (when it clears the neighbors arbor vitae wall 30-40 yards away) to 3pm when it becomes solid shade from our house. That is the hottest part of the day here, 3-6 pm daylight time. I think the shade at that time really helps. Ideally, for a tomato/pepper/eggplant plot, I would want full sun from daybreak to about 3 pm, then partial shade. I would consider that the garden lottery win, but I have never lucked into that. It might not be any better, but I'd love to try it.

May 4, 2020	#5
Koala Doug Tomatovillian™ Join Date: Dec 2017 Location: Detroit Posts: 688	I can only muster an average of about three-and-a-half hours of direct sunlight per day - up to five hours before the leaves fill in (mid-May) and down to two hours by the first of October. Too many large, mature trees... it is just the burden I must bear for living in this particular neighborhood. It also means I can't plant in-ground and have to use containers that sit on my concrete driveway (the only part of the property that gets any direct rays). The lack of direct sunlight makes the plants stretch and obviously would decrease the yield - as well as the size of the fruit - but I can still harvest a good amount of yummy tomatoes. I had more trouble before I switched to Texas Tomato Food - that stuff really made a significant difference. Everybody told me I couldn't grow tomatoes here, but I certainly can even with barely any direct sunlight. If the plants have the nutrients that they seek, and in the amounts that they want, then you'll still be able to get a decent harvest. I think Craig LeHoullier also used to have limited sunlight at his previous property in Raleigh. Maybe he can chime-in here on this subject.

May 6, 2020	#7
GoDawgs Tomatovillian™ Join Date: Feb 2018 Location: Augusta area, Georgia, 8a/7b Posts: 1,685	Many thanks for all of the replies! I need to set a reminder timer every day to go check the sun/shade status at various times. It appears that the time stamp feature on my camera is out of whack. I had been relying on that as I don't have a watch anymore and don't carry my phone in the garden.

May 6, 2020	#11
b54red Tomatovillian™ Join Date: Sep 2009 Location: Alabama Posts: 7,068	I have an odd shaped garden that is almost a triangle and the lower end of the triangle gets shade starting from between 2 and 4 every day depending upon the time of the year. I usually reserve that lower portion for later planted bell peppers which appreciate the shade in late summer and early fall but they don't produce as well and they tend to be leggy as well. When I grow tomatoes down in that portion of the garden my results are always disappointing with smaller fruit and actually less tasty tomatoes. The vines tend to be much thinner and fruit set is not as good as in more sunny locations. I wish I could convince my neighbors to take down some trees so I could go back to the sunny garden I had 40 years ago when the trees were very small. Bill

May 7, 2020	#13
slugworth Tomatovillian™ Join Date: Oct 2014 Location: connecticut,usa Posts: 1,152	I've had tomato plants with both plum shaped and round tomatoes (like anna russian) The plum got BER,the round ones were fine same age same exact plant.

May 26, 2020	#14
KathyDC Tomatovillian™ Join Date: Aug 2012 Location: Suburban Washington, DC (Zone 7A) Posts: 347	I plant in my back yard which has western and southern exposure, the sun rises and the house will shade the back yard until about 9am when it's up high enough that the back yard starts getting sun. They'll get full sun until about 3pm when the sun starts dipping down and unfortunately then all my neighbor's rampant derelict foliage starts getting in the way (in past years, I would get full sun until about 4pm, but unfortunately they don't take care of their property so another tree has been allowed to grow at the corner). After about 3pm I get dappled light/shade. This is the first year the sun will be stopping quite so soon, typically I have had until closer to 4pm. So I'll see how they do, but I anticipate they will be OK.