[maddave]

I've started picking my sweetcorn (swift) which I never grown before. Although being absolutely yummy, out of 6 of the cobs I have picked so far, none of them are completely full of corn to the tip. Most have at best about three quarters fully developed corn, with the rest being white undeveloped.  I've had to cut a lot of the cobs down in size.  None of the corn had been eaten by pests and what was developed was lovely and ripe and very delicious!

Is this normal and is there anything I can do next year to help prevent it? 

[snowdrops]

It means they didn't get pollinated thoroughly, may have been windy & the pollen blew away.

[kirpi]

I had this one year when I tried the Three Sisters approach (it was a couple of Butternut Squashes, French Climbing Beans and Sweetcorn in one bed) and some of the squash and the bean leaves were blocking the downward path from the top to the bottom of the sweetcorn stalks and I think the pollen was prevented from fully reaching the cobs.

Could there have been any obstructions preventing pollination?

[cadalot]

I shake the cobs once they are ready to pollinate and I have has 100% on the high levels and 80% on the lower ones. Next year I shall cut a few heads of and shake directly over the lower cobs to see if I can improved and I have read here that some people get the pollen on their hands and hand pollinate their cobs.

(I had to be carful how I explained that) 

[Goosegirl]

In the past when I grew mine outside, I had the same problem so they go in the greenhouse now and all get fully pollinated by tapping the stalks to release the pollen. I had 5 extra plants which went outisde this year and the kernels didn't swell even though it wasn't particularly windy.

[maddave]

Thanks all.. I didn't realise this was a pollination problem.  I did shake the pollen onto the tassels as much as could whilst it was out.  Obviously missed a few. I know next year I'll make sure to try and get every last one covered.