If plants have no consciousness does that make them any less worthy of care? Consciousness is nice, I'm glad I have some, but it's just one among many strategies that may help us replicate. Like flight or teeth or roses. An unconscious organism is different than a conscious one but not necessarily lesser in the way that matters: genetic survival.
It may be that consciousness is a net positive to us in that it lets us adapt to conditions more quickly. Our genes may last longer than plant genes as a result. But it also burdens us with destructive tendencies that threaten our survival. The jury is out.