How to Find Out if Your Gardener's Lying

I am an expert
Of the whole and cannot hope
To describe the part.

Probability,
Quantum physicists tell us,
Is amplitude squared.

You can't take the root
Of probability and
Derive amplitude.

You can't know the sign.
No one ever knows the sign,
Not even the sign.

I count trees in your garden
Grown from unearthly delights.