Whats too hot for tomatoes?

where_with_all · June 5, 2007

I think I read somewhere that when the soil temp gets over 85C the tomatoes stop making fruit. Is this true? or did I remember this wrong?

Is there an optimal temp for tomatoes to set fruit?

I am wondering if and when I should put cooling mulch around my plants?

No excuses for Brandywine this year-- High yields or BUST!!!!!

bcday · June 5, 2007

85C!!

I think you meant 85F

, and that's the air temp because of the effect that heat has on the pollen. I believe the optimum air temperature for tomato pollination is 70-82 F.

I found one source that says the optimum soil temperature for tomatoes is 75 F and mulching should start when the soil gets to 70 degrees.

felpec · June 5, 2007

Blossom drop can happen when night temperatures fall below 55 degrees F (which is supposed to happen here for the next few days :-(

Optimal temps are below 90-95 degrees F during the day and nights between 60-75 degrees F. These are air temperatures, not soil temps.

I usually start mulching about the third time we mow the grass, only because there's less weed seeds by then (mid-June).

feldon30 · June 5, 2007

I got most of my fruitset when daytime temps were 70-85 and nighttime temps were 45-60. Of course your mileage may vary. Humidity is also a huge factor.

TJS · June 5, 2007

How does humidity affect fruitset?

feldon30 · June 5, 2007

It causes the pollen to clump, preventing pollination.

captbobs · June 5, 2007

here in Puerto Rico I have great tomatos from nov. to may--day temp. 80 - 90 nights 65 - 75 - but now that days are 88 - 92 nights 82 - 86 nothing seems to produce---for 15 years I have tried them all--heatwave- solar set and so on. We have high humidity all year as I live a mile from the shore--But again had a great season. 15 gallons of romas in the freezer for great pasta sauce!! still a few ark-tr hanging on.

frankkj · June 5, 2007

I am by no means a pro with tomatoes like most of you, BUT, through the years I have noticed that when nighttime temps. exceed 80-85 degrees, the maters quit making more maters.

Please realize that this observation is made in south Louisiana, read that as high humidity................always. The daytime temps don't seem to bother them as long as they remain in the low to mid 90's and as long as the nighttime temps are in the high 70's, or very, very low 80s.

Not scientific, just my observations from years of "in ground" gardening.

Frank

June 5, 2007	#1
where_with_all Tomatovillian™ Join Date: May 2006 Location: Long Island NY Posts: 152	Whats too hot for tomatoes? I think I read somewhere that when the soil temp gets over 85C the tomatoes stop making fruit. Is this true? or did I remember this wrong? Is there an optimal temp for tomatoes to set fruit? I am wondering if and when I should put cooling mulch around my plants? No excuses for Brandywine this year-- High yields or BUST!!!!! __________________ Where With All on Long Island

June 5, 2007	#8
frankkj Tomatovillian™ Join Date: May 2007 Location: Louisiana Posts: 90	I am by no means a pro with tomatoes like most of you, BUT, through the years I have noticed that when nighttime temps. exceed 80-85 degrees, the maters quit making more maters. Please realize that this observation is made in south Louisiana, read that as high humidity................always. The daytime temps don't seem to bother them as long as they remain in the low to mid 90's and as long as the nighttime temps are in the high 70's, or very, very low 80s. Not scientific, just my observations from years of "in ground" gardening. Frank __________________ Old and Wise? Or maybe just getting old?

June 5, 2007	#2
bcday Tomatovillian™ Join Date: Jan 2006 Location: NY z5 Posts: 1,205	85C!! I think you meant 85F , and that's the air temp because of the effect that heat has on the pollen. I believe the optimum air temperature for tomato pollination is 70-82 F. I found one source that says the optimum soil temperature for tomatoes is 75 F and mulching should start when the soil gets to 70 degrees.

June 5, 2007	#3
felpec Tomatovillian™ Join Date: Mar 2006 Location: Zone 5/6 New Jersey Posts: 122	Blossom drop can happen when night temperatures fall below 55 degrees F (which is supposed to happen here for the next few days :-( Optimal temps are below 90-95 degrees F during the day and nights between 60-75 degrees F. These are air temperatures, not soil temps. I usually start mulching about the third time we mow the grass, only because there's less weed seeds by then (mid-June).

June 5, 2007	#4
feldon30 Tomatovillian™ Join Date: May 2006 Location: Rock Hill, SC Posts: 5,346	I got most of my fruitset when daytime temps were 70-85 and nighttime temps were 45-60. Of course your mileage may vary. Humidity is also a huge factor.

June 5, 2007	#5
TJS Tomatovillian™ Join Date: Apr 2007 Location: Chas SC Posts: 70	How does humidity affect fruitset?

June 5, 2007	#7
captbobs Tomatovillian™ Join Date: May 2007 Location: Puerto Rico Posts: 13	here in Puerto Rico I have great tomatos from nov. to may--day temp. 80 - 90 nights 65 - 75 - but now that days are 88 - 92 nights 82 - 86 nothing seems to produce---for 15 years I have tried them all--heatwave- solar set and so on. We have high humidity all year as I live a mile from the shore--But again had a great season. 15 gallons of romas in the freezer for great pasta sauce!! still a few ark-tr hanging on.