You a.lso may need more phosphate. You might want to try Miracle-Gro.

The leaves of tomato plant should look terrible so that all the strength goes to making seed via the flower & the fruit. If your tomato leaves look vibrant green & spectacular you won't set fruit very well. A traumatized tomato plant puts out lots of flowers as a survival mechanism.

My experience has been that, while tomatoes do need heat, they don't set and hold blooms very well when the temperature exceeds 90 degrees. You might try gently hand pollinating them by jiggling each bloom. Sounds silly but the blooms try to curl up and resist pollination.

Tomatoes need a lot of sun, a lot of heat and adequate fertilizer. They require average to a lot of water, as long as it drains completely.

Tomatoes need a lot of sun, a lot of heat and adequate fertilizer. They require average to a lot of water, as long as it drains completely.

[gardeningsolutions.ifas.ufl.edu]

What type of tomato are you growing?

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The other suggestions are good, tomatoes are actually perennials and some varieties won't fruit unless stressed in some way. You need to fool them into thinking they need to reproduce before they die. Shade or withholding water are what I'd try first if the plants are healthy and devoting a lot of energy to leaf growth.

Because it is too hot where you are. Can you erect a little shade ?

Fertilizer