The exponential growth can be expressed as

$W_{l}=W_{0} e^{rt}$

Where,

$W_{l}=$ Final size(weight, height, number, etc.)

$W_{0}=$ initial size of the beginning of trhe period

$r =$ Growth rate

$t =$ Time of growth

$e =$ base of natural logarithms

Here, $r$ is the relative growth rate and is also the measure of the ability of the plant to produce plant material, referred to as efficiency index. Hence, the final size of $W_{l}$ depends on the initial size $W_{0}$