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I usually plant my onion sets straight into the ground in spring, covering with a mesh frame to keep the birds off until they’ve sprouted and developed a good root system to anchor them in. I harvest a decent crop but I do get a number of smallish bulbs despite my soil being well nourished.
Today I planted half my onion sets in module trays filled with compost (‘Red Baron’ and ‘Stuttgarter Giant’), growing them on in my unheated greenhouse. The other half will be planted out into the ground, in the usual way. The idea is to give half the sets a bit of a head start, an experiment really.
I’m curious to see if this makes any difference to the overall size of bulbs come harvest time, compared to the sets planted straight into the ground a month or so later.
I’ll let you know how I get on.
Might give this a go this year. Thanks for the idea.
I’m going to go this too :D
This year we are going to try the opposite. Last year we started quite a few things ahead of time and compared them to what we later planted straight in the ground. It seems the transplanting set the starts back enough that the directly planted seeds caught up and some plants surpassed the transplants. So this year we are going to experiment with some earlier in the ground under cover (probably hoops). Looking forward to seeing what results you find.
A great idea to start them off like this. I do love the colour of those red ones, it’s beautiful.
I’ve never tried starting them off this way before, I think I will do the same.
I simply don’t have room to start off them like that so sow mine direct. I’m growing red Baron for the first time so it’ll be interesting to see how we both get on with them. xx
Brilliant idea. Looking forward to your results. Our onions have struggled the last few years because of water logging. We always do our shallots in cells and they work well. Malc
I’ve seen quite a few people do that this year, sadly I just dont have the space to seperate my onions, so the sets are already in the ground (have been since Nov last year) and are doing well. I am also growing from seed this year so they are in the conservatory. I will be watching to see how they do and might try this next year (if we have space!)
Nessy
It will be interesting to see how this works out. I had a wide range of sizes in my seed-started onions last year and then this winter I read that spacing affects size. I tend to crowd things so that may have been it, but on the other hand I did get quite a few larger bulbs.
Good luck with them!
I give my sets a generous amount of space, but I still get a number of small bulbs, some of them really small! Particularly with white onions.
Tempted to follow suit and try in our unheated greenhouse. I always grow stupid amounts of onions anyway and find a varying amount bolt far too easily. This might hold the key to stopping that at least.
We’ve done just the same thing