For most yellow squash varieties—like straightneck or crookneck—the sweet spot is 4 to 6 inches long. That’s about the length of a good, hearty banana, but way less slippery. At this point, the skin is thin, the seeds are tiny, and the flesh is sweet and buttery.
If you wait until it’s a 10-inch beast, you’ll have to start calling it a baseball bat. Trust me, no one wants to chew on a baseball bat at dinner.
Check the Color and Shine
Another clue: your squash should look bright, glossy, and firm. A dull, dull surface means it’s starting to age—like a tired actor after a long season. Squash that’s still ready to pick will have a little sheen, like it just got a spa facial.
If you press your fingernail gently into the skin, it should feel firm but give a tiny bit. If it feels like a rock, it’s underripe. If it feels mushy or too soft, it’s already starting its journey to the compost heap.
