Why are my tomatoes setting fruit at 102 F?

I planted my tomatoes in the first week of April expecting cool weather until late May or early June. That is pretty typical weather around here. Unfortunately the hot weather started hitting in early May. The temps this past week were 102 daytime, 80 night time.

My tomatoes grew and bloomed a little through April, but stopped when the hot weather hit in May. I had very few fruit on the plants and had just about given up on the spring season. Three days ago, they started blooming again and setting fruit even with the high day and night temps. Even my Brandywines are setting more fruit. The one that really has me curious are the Stupice plants. They didn't set any fruit in the cool early spring. I thought they were supposed to be an early tomato. Now at 102 degrees, they are blooming and setting fruit. The Prudens Purple have put on about five fruit in three days.

We are supposed to have a rainy spell later this week with high temps possibly only in the 80's. Please don't tell me tomato plants can forecast weather changes up to a week in advance of the change. If I believe that, I will take my crystal ball and my Ouija board to the garden with me.

Ted

[discrepancy]

They're trying to confuse you. Next thing they'll do is grow tomatoes in the shape of bacon rashers, but don't be fooled.

[Close enuf]

Is it less humid now than it was earlier in the year?
That would be my only guess

No, the humidity right now is only 44%. It typically goes down during the heat of the day. When it starts cooling a little later in the evening, it will go back to the high 60% level. That has been pretty normal for a few weeks.

Ted

[Dewayne mater]

That is crazy, especially the Stupice not setting early. I think I've picked 2-3 dozen from one Stupice plant and it probably has that many more on it now, and I think more coming (and I've lost several to BER...crazy prolific plant). The fruit are getting smaller though, and they started off smallish. I've had some recent fruit set on Indian Stripe, black and brown boar, and black cherry seems like it is still rocking. The only think I can think of is we did have some rain one day that provided about about 18 hours of quite pleasant temperatures and we've had some overcast, but still hot days. I'm thinking some flowers were new enough to not have been heat blasted and they set fruit in that small window, but who knows?

[b54red]

Enjoy your good fortune while it lasts. Keep up with the ones that do set fruit in the heat and try some of them as fall tomatoes; that's what I'm trying to do. I just planted the seed for about 30 varieties for fall and used only ones that are still setting fruit or that have been successful in past fall seasons.

[desertlzbn]

I have successfull fruit set up until the nite time temps stay above 90+. I also spray my plants down with water at night, that really helps with fruitset too. I think as long as the blooms have cool enough temps for the pollen to not be sticky you will get fruitset.
My biggest problem has been with Early blight. It has totally stressed all of my plants and I had massive blossom drop because of it. For the ammount of plants I have, I sure don't have many fruit. Next year I plan on using the Actovanate (sp?) and Mycco.

Originally Posted by b54red

Enjoy your good fortune while it lasts. Keep up with the ones that do set fruit in the heat and try some of them as fall tomatoes; that's what I'm trying to do. I just planted the seed for about 30 varieties for fall and used only ones that are still setting fruit or that have been successful in past fall seasons.

I have some Black From Tula and JD's Special C Tex seedlings growing which I will plant near the end of June for fall tomatoes. I planted some Sweet Carneros Pink a few weeks ago and they are now about 16" tall and starting to grow pretty fast. I hope they will make it through the summer and also be fall tomatoes.

I also have a misting system on a stand which I will try in the garden to lower the daytime temps on the tomatoes. It will be interesting to see if it works. The mister breaks the water droplets into what looks like fog. It doesn't get anything wet, but does lower the temps around it as it evaporates.

I installed a misting system around a covered deck when the temp was 102 F. It lowered the temp on the deck to 78 F and nothing was wet.

Ted

[AZRuss]

I agree with b54red... enjoy your good fortune while it lasts. I'm wondering if you have lots of bees around. Last summer I had a couple of varieties set fruit in July (105+ day, 90+ night). There were a couple of flowering basil bushes nearby swarming with bees. I attributed the fruit set to them. Unfortunately, the constant heat caused those tomatoes to be small, hard and dry. In other words, inedible.

Your misting system is wonderful, and I'm sure you'll have good results with it.

[chalstonsc]

Ted,
Can you give us some details about your misting system, such as make, model, cost, etc. You've got me interested!
Tom

Originally Posted by chalstonsc

Ted,
Can you give us some details about your misting system, such as make, model, cost, etc. You've got me interested!
Tom

I bought both at Sams Warehouse. The system in the garden has two mist heads and the heads are on top of a four foot tall plastic pipe that is bent into the shape of a pretzel. The shape provides the base where the hose attaches at the base. It cost $9.00. I think I have seen them at Walmart or Home Depot as well. I just determine which way a breeze is blowing and set it for the mist to move over the tomatoes. You can move it around the garden as needed.

The deck system cost $29.00 and comes preassembled with 17 mist heads on 30' of hose. It comes with little plastic clips which you nail into the top frame around the deck on both sides of each mist head. It took me about an hour to install the system and then I hooked a garden hose to it and turned the water on. It immediately started cooling the deck. I brought a wall thermometer out and checked the temp in the shade. It was 102 F. I then checked the temp on the deck and it was 78 F. It uses very little water. When I turn the water off at the tap, it takes a couple of minutes for the hose to depressurize and the heads to stop misting. You do need at least 60 psi water pressure for it to work properly. It works up to 80 psi system pressure and would probably blow apart above 80. All the mist heads are shrink fit into the hose. It could also be easily adapted to work in a large garden, but it needs to be elevated to about eight feet.

Ted

My bees haven't shown up this year. Last year, I had a ton of bees because I left my squash plants uncovered. This year, I put hoop tunnels with netting over my squash beds to stop the squash vine borers. It also keeps the bees away. I feel like the first scout bee that came around went back and told his friends that the friendly gardener from last year isn't as bee friendly this year.

Ted