"Richard Wright" wrote in message

In my area of Sydney (inner) daffodils mostly come up non-flowering
in
the second season after planting.

Sydney isn't naturally cold enough for daffodils. You need to lift
them each year and put then in a paper bag int he crisper section of
the fridge for 6 weeks before replanting them.

Does anybody know whether the bulbs ever produce flowers in a season
after one in which they have been non-flowering? I suspect that once
they have been non-flowering then they will never flower again.

No they just need cold (at least in Sydney). They will reflower if
treated right.

I did read about digging them up in autumn and putting them in the
fridge for a couple of months. That didn't work for me.

How long did you put them in the fridge for and did you put them in a
sunny spot when you replanted them? And they don't like to be
overfed.