Onion growth stopped early

[SMT]

I've just had my first year growing in a 24 x 16ft polytunnel. The mangetout, potatoes and pumpkins did really well, but I had a disaster with my onions. They just seemed to stop growing very early on. Turned out a little larger than a pickling onion.

Would any one have some suggestions as to why they would have stopped so I can prevent it from happening again next year?

The year before I grew them outside with no problem and didnt have to buy an onion all winter. This year they have already gone

Many thanks for your time from a newbie wishing to learn more.

[zazen999]

The only thing I can think is that they got too warm too early and thought it was time to stop growing.

I'd grow onions in a polytunnel through the winter, but it is far too warm for them in the summer.....I think anyway

[Pies]

I doubt it heat as i read many blogs of onions being grown in polytunnels.I suspect the onions dried out.Did you water them regularly ?

[SMT]

lol. I thought I did. The pumpkins I grew were atlantic giants so required watering nearly every other day. I watered everything at the same time. I couldnt have given them too much do you think?

It did get very hot some days when we did actually see signs of a summer.

[Two_Sheds]

My onions were a mixed lot (they are every year). Half of them grow nice and fat, the other half stay small and useless.

Last year I know my small onions were down to poor feeding. I grew half on good soil and half on poor sandy soil. The poor half barely grew at all.

But this year they all went in the same patch, and I still ended up with a lot of very small onions. Perhaps something wrong with the onion set itself?

[SMT]

Thanks btw for the replies

It has crossed my mind the feeding might have been an issue. The ground had not previously been cultivated before (lawn) so I bought in fresh topsoil with a compost/manure mix. I also broadcast some chicken pellets over the polytunnel as it was a rush to get the poly up in time before planting.

I have read somewhere that its best not to manure onions the same year as planting. Then again I've seen info to say they need a lot of manure. I dont know what to believe. Anyone know whats best?

[gojiberry]

I often have problems with onions and didn't know if it was a problem with the Ph level. I know that some plants can't take up nutrients if the Ph is wrong and am wondering if onions are one of them.

Ian

[Two_Sheds]

Make sure you don't plant the set too deep.

Also, this chap (who seems to know his onions) says "not to use too much organic matter"

[SMT]

Thankyou everyone.

The link is a good read Two sheds, thankyou.

Fingers crossed for next year.