GardenBanter.co.uk - Cabbage & Cauliflower

Hello group
I hope you all had your best cropping year as I have(partially)
My first two years gardening a veg plot were a learning for me and to
get what I thought was a good soil, and I thought I had it.

I live in S****horpe which is in UK South of Hull

I have had a great third year with my veg plot: potatoes, beans,
tomatoes, herbs, onions, garlic, shallotts etc.

My cabbages and cauliflowers however have failed for two years
running! In the first year I had cabbage maggot, and I got over that
problem this year by using "collars" to stop them laying eggs at the
roots.

THIS year they have looked lovely and green, but have not "hearted up"
despite feeding them at regular intervals with blood/fish/bone and
also growmore.

3 small plots, one with blood/fish/bone the second with growmore, the
third with both (and a couple with no fertilizer at all...they are
useless)

I have rung the changes so that my own cultivations and shop bought
are in shared and different beds to eliminate fault but all are the
same.

What can I be doing wrong?

Thanks for reading this lengthy text.
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