Onions from seed.

[Aberdeenplotter]

onions tend to thrive best when the roots are tight in the pot. Obviously there will come a time when they absolutely must be potted on. With my big onions, I start them off in cellpacks or small pots, then move them into 2½"-3" pots, then into 6" pots then into a 6" hole that the rootball fits in to exactly.
(I bury an empty 6" pot up to the top and then remove it at final planting time and drop the rootball into the empty space.)

[vikkib]

Looking absolutely great Vikki. My main concer with the cardboard tubes is that you may get fungul infection setting in. I would be for potting them on into small plastic pots before that happens. Best not to break the roots if that can be avoided. It won't stop them growing but it may give them a wee set back which can leed to bolting.

If you do decide to move them to the unheated greenhouse, harden them off gradually before moving them.

Thanks very much for the info AP; the tubes are looking less than pristine already!

That's a job for me for the weekend then!

May I pick you brain further and ask what size pots would you recommend?

I'd rather avoid re-potting again before they get planted out if possible...

Can I get away with 6cm/2 1/2" like these:
PK(100) 6CM (2.1/2") SMALL SEED / CACTUS PLASTIC POTS | eBay

Or would I be better off with 7cm/3" like these:
PK(300) LIGHTWEIGHT 7CM SQUARE BLACK PLANT POTS NEW | eBay

I'll shop around when I know what I'm looking for, I don't have two hundred of either of the above sizes!

[Aberdeenplotter]

Looking absolutely great Vikki. My main concer with the cardboard tubes is that you may get fungul infection setting in. I would be for potting them on into small plastic pots before that happens. Best not to break the roots if that can be avoided. It won't stop them growing but it may give them a wee set back which can leed to bolting.

If you do decide to move them to the unheated greenhouse, harden them off gradually before moving them.

[vikkib]

Mine are going great guns under the lights, about 3" high now (apart from the one's I snapped when I put the supports in!

I'm going to keep them under the lights until I need the space for other things then they'll go into the unheated greenhouse - I'm nervous of them getting frosted so I'll pop fleece over them at night.

My main concern at the moment is that I sowed them in loo rolls cut in half so there's no base to them and the roots are already heading out the bottoms!

Will this cause a problem by the time I come to plant them out? Should I be trying to stop them getting tangled or can I treat them like leeks and just pull them apart when they need to go outside?

Edit - piccie added!

[Potstubsdustbins]

Well I have potted on into 3" pots and the growth rate continues.


Potty

[Lando]

I like your mini stakes AP. I think even I could make them

[Bigmallly]

Brilliant........................I'm on the case and following the trail

There's a separate thread for that sort of talk.............

[Ger-annie-um]

Still time to get decent onions so get cracking. Root trainers are fine. With show onions, I'm looking to be harvesting at the end of July to give the bulbs at least 4 weeks ripening time before my first show. That time also allows the necks to dry out totally so that they can be tied tightly with natural rafia.

Brilliant........................I'm on the case and following the trail

[Aberdeenplotter]

Oops I've only just sowed my onions (kelsae) - I hope they get to a decent size???

Is it too late for me to join in..........my problem is I can get the onions to grow (from seed) and they get to a reasonable size but I seem to have major issues with lifting, drying and storing. I'm hoping this step by step, hopefully idiot proof - me being the idiot will show me the right way of doing things. One question, can I transplant the seedings into rootrainers, I have loads of them not being used.

Still time to get decent onions so get cracking. Root trainers are fine. With show onions, I'm looking to be harvesting at the end of July to give the bulbs at least 4 weeks ripening time before my first show. That time also allows the necks to dry out totally so that they can be tied tightly with natural rafia.

[Ger-annie-um]

Is it too late for me to join in..........my problem is I can get the onions to grow (from seed) and they get to a reasonable size but I seem to have major issues with lifting, drying and storing. I'm hoping this step by step, hopefully idiot proof - me being the idiot will show me the right way of doing things. One question, can I transplant the seedings into rootrainers, I have loads of them not being used.

[Matt94]

Oops I've only just sowed my onions (kelsae) - I hope they get to a decent size???

[Thelma Sanders]

I dunno - you're sposed to keep them at an even temperature Huh! with the way the outside temp is fluctuating?

[Aberdeenplotter]

rofl, so you left me to look like a twit instead, love it . Should be no possibility of it being white rot in good quality compost.

[Potstubsdustbins]

Potty, make the suggestion

Like you AP I thought about damping off, or maybe white rot. But as this is my first attempt at growing from seed I didn't want to make myself look a twit.

Potty

[Aberdeenplotter]

Pics from right to left of

1. seedlings just coming out of crook stage ready to prick out

2. Seedlings pricked out

3. Seedlings with mini stakes now needing larger stakes. Note the withered shoot on the corner onion which was the original first shoot with seed pod attached.