You can create leaves using the “Standard leaves” option.
Just select the rectangle and set the “Length/Width” proportion to be equal to “15”, for example.
Besides, you need to set the path length, to make it equal approximately to the length of a needle and specify the same value for the path step.
The plant will be calculated quickly, and the needles will have the least number of faces.
Please see picture:

Conifer leaves

Applicable to: