As covered in section 1.1, we deliberately avoid treating
seasonality as a calendar grid. This section looks at exactly
why: the same calendar date can mean very different things
from one year to the next.

An unusually warm spring can bring emergence and flowering
weeks earlier than the previous year. A cold, late spring can
delay things just as significantly. The plants you found ready
to pick on a particular date last year might still be dormant,
or already past their best, on the same date this year.

A particularly wet year tends to produce lusher growth and
often better berry and mushroom yields, especially for fungi,
which depend heavily on consistent moisture. A dry year can
mean smaller, scarcer harvests even from reliable patches.

Two patches not far apart can experience meaningfully different
conditions — a south-facing slope warms faster than a shaded
north-facing one, a sheltered garden corner stays milder than
an exposed field edge. This is part of why localising,
as covered in section 2.2, matters more than general seasonal advice.

Fungi are especially sensitive to year-to-year weather variation.
A good mushroom year, with the right combination of warmth
and rain at the right time, can produce abundance that a
drier or oddly timed year simply won't repeat. Don't be
discouraged if a reliable mushroom spot disappoints one year —
it's often the weather, not the patch.