When to harvest: read the plant, not the calendar
Seed-packet "days to maturity" is a guess. The plant tells the truth: tomatoes are ready when the shoulders turn from glossy to slightly matte and the fruit gives a little, garlic when the bottom third of leaves brown, winter squash when a thumbnail won't dent the skin.
Read the quick guide
Leafy greens: take outer leaves any time after they reach palm size — cut-and-come-again beats pulling whole heads. Root crops: brush soil off a shoulder and peek; carrots sweeten after a light frost. Beans & peas: pick every 1–2 days once they start, because pods left on the vine tell the plant to stop producing. Onions: wait for tops to flop on their own, then cure two weeks somewhere dry. Melons: a ripe cantaloupe slips off its stem under light pressure and smells sweet at the blossom end. Harvest in the cool of morning and get produce out of the sun fast — most quality loss happens in the first hour.