Allotment Gardening Advice Help Chat

Growing => Grow Your Own => Topic started by: andyww2013 on July 16, 2019, 19:47

Title: Failed Onion Crop
Post by: andyww2013 on July 16, 2019, 19:47

Hi,

So another year and another failed onion crop.  Decided to mulit sow this year, the idea being to take some spring onions and let remaining ones grow bigger.

Was doing reallly well, but now they are looking far from healthy and very small.

Any idea what the problem might be?

Is all hope lost?

Title: Re: Failed Onion Crop
Post by: JayG on July 16, 2019, 20:52

May well have suffered from an attack by one of the many allium pests around these days.
Not dead yet - a liquid feed might help them recover and bulk up a bit (my shallots have struggled similarly for the last few years but actually cropped quite well last year.)

Title: Re: Failed Onion Crop
Post by: Aidy on July 16, 2019, 22:09

My first thought is the same as JayG. I would not sow then pull small spring onions as the risk of onion fly and other would increase.

Having said that a lot peeps on our site have struggled this year.
I always grow mine under sheet to reduce weeding etc to keep the risks low, water regular and feed with Maxicrop seaweed every two weeks.

Title: Re: Failed Onion Crop
Post by: Dev on July 17, 2019, 03:20

Have you pulled any yet and looked at the roots. It could be onion white rot - a white fungal growth on the roots. If it is you won't be able to grow alliums on that piece of ground for 5 to 7 years. I hope for your sake its not the dreaded rot. Other than that try JayG's idea.

Title: Re: Failed Onion Crop
Post by: Goosegirl on July 17, 2019, 10:31

I'm a fan of Maxicrop because it can give a boost when plants look to be struggling. Onions don't like competition from weeds so I'm wondering if planting them in a clump puts more stress on them.

Title: Re: Failed Onion Crop
Post by: andyww2013 on July 21, 2019, 18:57

Having spoken to some more experience gardeners at the allotment, the general conclusion is these have succumb to something called 'Downy Mildew'

Need to do a little more research but it appears to be terminal.

Title: Re: Failed Onion Crop
Post by: grinling on July 21, 2019, 19:36

Mildew is found on the leaves, it is powdery white, you can wash the leaves with washing up water.
The weather has been warm and wet which increase the risk of this.
Change where you buy your shallots sets from and rotate the crop.
Have a check for white onion rot,some large suppliers will sell onion sets with this.

Title: Re: Failed Onion Crop
Post by: JoshP on July 23, 2019, 15:02

Looks like downy mildew to me. Devastating to onions