What temperatures stop production?

dfollett · April 27, 2013

Heat is not a problem here, so I know nothing from experience of tomatoes not producing because of heat. Biggest problem here is cold soils and late and early frosts. I know from reading that when heat gets too intense, tomatoes stop producing new blossoms. I am experimenting with tomatoes outdoors in Earthtainers with a make-shift greenhouse around the top.

So far, it is working great. They've survived 8 nights below 25⁰ over the last month (as low as 15⁰) and are growing very well and setting fruit. My concern now is not cold nights, but daytime temperatures. I’m relatively high elevation (5280’) and things cool off significantly when the sun starts to set. However, during the middle of the day (12:00 – 3:00 pm) temperatures inside where the tomatoes are climb to between 90⁰ and 95⁰ - and I’m sure that over the next month they will hit 100⁰ to 105⁰ or so. It is only that hot for about three hours then quickly drops to 70’s then gradually cools off to 45⁰ to 60⁰ each night (on the sub-20⁰ nights, they get down to the high 30’s).

My question is: Do I have to worry about them not producing because of those few hours on the sunny days where the temperatures spike?

April 27, 2013	#1
dfollett Tomatovillian™ Join Date: Dec 2012 Location: Utah Posts: 693	What temperatures stop production? Heat is not a problem here, so I know nothing from experience of tomatoes not producing because of heat. Biggest problem here is cold soils and late and early frosts. I know from reading that when heat gets too intense, tomatoes stop producing new blossoms. I am experimenting with tomatoes outdoors in Earthtainers with a make-shift greenhouse around the top. So far, it is working great. They've survived 8 nights below 25⁰ over the last month (as low as 15⁰) and are growing very well and setting fruit. My concern now is not cold nights, but daytime temperatures. I’m relatively high elevation (5280’) and things cool off significantly when the sun starts to set. However, during the middle of the day (12:00 – 3:00 pm) temperatures inside where the tomatoes are climb to between 90⁰ and 95⁰ - and I’m sure that over the next month they will hit 100⁰ to 105⁰ or so. It is only that hot for about three hours then quickly drops to 70’s then gradually cools off to 45⁰ to 60⁰ each night (on the sub-20⁰ nights, they get down to the high 30’s). My question is: Do I have to worry about them not producing because of those few hours on the sunny days where the temperatures spike?