When planted too soon, the heads mature in weather that is too warm - which leads to weirdness. A Q and A on the University of Illinois website tells exactly what happens:
Q. What causes leaves in the head and separation of the head into loose, smaller curds?
A. These conditions are caused when cauliflower matures during hot weather. Try to time maturity dates of cauliflower to minimize the risk of extreme heat as the heads form.
As a gardener who has seen this in action in her own yard, I know firsthand that this outcome is a huge disappointment, mostly because the flavor is affected, too. This is what can happen when cauliflower is planted in August. However, later plantings run the risk of not having enough time to mature before colder weather sets in. The window of opportunity is a small one, and it can be hard to gage.
|The cauliflower in the lower left corner is pink and "curdled."|
Have you ever been driving down the road when a squirrel races out right in front of your car, and then while you are busy applying your brakes and mentally urging the squirrel to keep going - please! - the squirrel makes a heart-stopping dramatic pause smack in front of the car, and then, at the last second, when the car is so close that you can't actually see the little animal anymore, it darts onward, but the only way you know it finally raced away is that you didn't feel its little body go under the wheels?
Growing cauliflower can seem a little like that. Lives aren't at stake (thank goodness), but the drama is there, unfolding in slow motion. This year, I ended up with a decent amount of good cauliflower and a little weird cauliflower.
In other words, my timing wasn't perfect, but it wasn't awful, either.
Some of this year's weird cauliflower turned pink. I've done quite a bit of searching for possible causes, and it turns out that some cauliflower has more pinkish-purple pigmentation than other cauliflower.
According to the University of Illinois (see earlier link, above), if I had done a better job of pulling leaves over the heads to keep the sunlight off as they formed, the pink might not have appeared at all. In other words, the pink was unexpected, but it's not outside of the realm of normal for cauliflower.