skinny sweetcorn

I have three different stages of sweetcorn.  My first is exactly the same as yours, very skinny and light green but with what look like healthy corns growing.

In my front garden I have very healthy looking dark green thick stemmed tall plants but with no cobs or tassels growing.

Somewhere in the middle I have a rather haphazard bed at the allotment from the same sowing as the front garden ones, some of which have survived, some haven't and they are about a third of the size of the ones in the front garden.

I am waiting to see which of the three is the most productive in terms of delicious cobs!