Short answer: yes, with conditions. Columbia Road is one of the few London "attractions" that is not performing for you; it is a working flower market that happens to be beautiful. That is exactly why it is worth seeing, and exactly why it disappoints people who turn up at noon expecting a curated experience.
Here is the honest assessment, both directions.
The case for going
It is the real thing. The market has traded on this street since the 1860s. The traders are selling flowers to Londoners who need flowers; the shouted prices, the banter and the 2pm discounting are commerce, not theatre. In a city increasingly full of purpose-built "experiences", that distinction is worth a Sunday morning.
It costs nothing. Free to visit, and if you do buy, the flowers are roughly half florist prices, dropping further late in the day. Compare that to almost any other London morning out.
The street is as good as the stalls. Sixty independent shops behind the market: galleries, delis, vintage dealers, proper pubs. Even flower-indifferent companions find something.
It anchors a perfect half day. Fifteen minutes' walk from Brick Lane, which means the market slots into the best free itinerary in London. We have mapped it in our Columbia Road to Brick Lane walk.
The case against
The crowds are genuinely bad at peak. From roughly 10.30am to 1.30pm in spring and summer, the street is a slow single file. If you hate crowds and can only come at midday, this may not be for you.
It is short. The market is one street, 400 metres. If you arrive expecting a Borough Market-scale destination, you will be done in forty minutes and wondering what the fuss was. The fix is pairing it with the surrounding area, not lingering.
Sunday only, morning weighted. No flexibility: miss the window, miss the market. Travellers on a tight itinerary sometimes cannot make the timing work, and there is no consolation version on a Tuesday.
You cannot take flowers home on a flight. Visitors buy less than locals for obvious reasons. If you cannot buy, you are coming purely for atmosphere and photographs, which is fine, but calibrate expectations.
Who will love it
Anyone who likes markets more than museums; photographers, especially early; gardeners and plant people, who should bring a bag and a budget; and anyone building a lazy East London Sunday around brunch.
Who should skip it
Anyone allergic to crowds who can only visit midday in May; anyone expecting a food-market scale of destination; and honestly, anyone whose Sunday is already fully booked, because the market rewards unhurried visits.
How to make sure it is worth it
The difference between a five-star and two-star experience here is almost entirely timing. Go before 9.30am or after 2pm, know how you are getting there (public transport, not a car), and read the complete guide so you know the rhythms before you arrive.
Verdict: worth it, comfortably, for the price of an early alarm.