Potting Up Giant Onions

Potting Up Giant Onions

At this time of year the one plant that is already under way are the giant onions. They were planted 11 days ago and are ready to pot up into the first pot. The seedlings are at the crook stage having just straightened out. 

There are lots of different options for the early stages. On of the popular composts is the Levingtons F2 + S which is a quality compost for a range of uses. It is an ideal seed compost and is the one I use later on for growing quality carrots.

Though I have used this in the past I am taking a different route this year. I am potting the seedlings up into Canna Coco Professional Plus mixed with some perlite. 


Canna Coco Professional Plus is made from coconut fibre. Canna Coco Professional Plus provides an environmentally safe and economical growing medium which holds lots of water yet allows air to move freely through it providing oxygen for the roots.

When potting up seedlings it is important that the roots are not damaged as this would impact the early plant development. One tip which I use is to soak the compost which makes it simple to extract the roots without breaking them.

With the space I have I have potted up about 30 seedlings and I have a number of plants that I have been growing from pips. I will need to go through a vigorous selection process until I have 8 or 10 plants which I will grow to maturity. Even at this stage there were a few seedlings that were of poor quality so I discarded those.

Newly potted Seedlings at 11 days , the second image shows the seedling standing up overnight.

Onion pips, all planted at the same time but developing at different rates.


The author Nick Pengelly who is a Director of JustSeed Ltd has had success at growing a variety of giant vegetables as well as an increasing range of interesting and unusual plants. He also has the National Collection of Cheiridopsis!

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