I always plant a crazy vegetable garden and cram far more vegetables into a 10 foot by 10 foot piece of lawn than is healthy. Both last year and this year, I bought a few broccoli seedlings, on a whim, with the intention to convert my own palate to a broccoli-loving from a broccoli-hesitant one.
Last year, I exalted when the first green brassica head of appeared from between the finger-like leaves. And I waited and waited for that head of broccoli to reach grocery-store proportions, only to discover one morning a yellow flowery head of broccoli where the green edible one had been a few days earlier.
This year, determined not to make the same mistake, on June 9th, I harvested a puny little 2 inch head of broccoli only to wonder if it would have gotten bigger. Surely it wasn't done growing. So how does one know when to pop the head off this green beauty?
Referring to this website, I found the answer:
A "ripe" head of broccoli should be a deep green, 4-7 inches in diameter and the outer florets should be about the size of a match head.
Good luck and happy gardening.
Yours truly, Miss Greenish Thumb