Help ... What is happening to my cucumber?

it is looking better.

 

So inquiring minds want to know what you did?

 

It could be leaf scorch, it will recover but don't over water, cucumbers don't like it.

 

Thanks Carolyn, it is growing fast now

Dirtmechanic this is what I did

I used this formula for my all purpose bug spray,
Veg Oil 1 tablespoon
Vinegar 20 ml
Soap 75ml
Baking Soda 20 gm
Water 5 Liters

Thanks Logan.

 

I need to make note of this, I think I should spray some of the plants like tomatoes and cucumbers a couple of times during the summer, as a preventive measure, or is it better to only spray if necessary.

 

I don't spray at all.