Coconut trees, our value fu(i)nders?

This is the Coconut tree I can see from My Balcony

 The above is a coconut tree (I know I don't need to name it). But, I often wondered how long does it take for a coconut tree to grow its prime stage a time of 15-20 years. A quick Google search told me that. You can use the wiki Gadget I added to this blog.

My father and I had a discussion regarding Coconut trees, and he says its a long terms investment. We have a small ancestral land in our village which we lease out for Agriculture, with lease renewal every year. My dad thinks we should invest in the land but none of us have enough time to look after it (because it takes 15-20 years). Then we both thought about it. It takes the same amount of time to raise one's own son. That means if we start planting a plant everytime a child is born, we already would've had many Coconut plants, and would definitely have had the opportunity to contribute. 

The funny thing is, my dad questions, the Coconut tree at least provides coconuts to drink water, what does a son/daughter do? Do they really take care of their elderly ? I don't think so, but do they really leave it to God ? That's not true either. So, where exactly does a Coconut tree stand in terms of value in comparison to a grown human being. I fail to see the difference. I think man can't even withstand a cyclone while a tree can. So, what have you go to say ?