Onion Set Problems

[tottieheed]

Hi everyone again

I got my first ever onion sets about a week ago and after watching some youtube clips on what to do with them I opted to stick them in some compost in a seed tray to give them a head start. I have put them in the conservatory as it is still cold in there at this time of year. I gave them a little water as the compost was very dry. My plan was to leave them for 2 or 3 weeks and then plant them out

They have been there now for around 1 week and I have noticed a bit of white mould on the surface. I think this is growing from the compost rather that the onion sets but have no experience and wonder if there is anything I should do as I don't want them to rot or die.

Any thoughts?

[tottieheed]

[Ellen K]

Is it on the onion or on the compost surface?

It doesn't sound like onion white rot as that starts at the the root vase.

I wouldn't worry too much but no harm in scraping it off if you can.

[queenbee]

You say your conservatory is cold at this time of year, I too have a conservatory, no heating at the moment, but I have noticed that on a sunny day at this time of year the temp. can really rise, could the fluctuation be the cause of the mould. I would put them outside under fleece and extra covering if frost is forecast. Good luck with your Onions for the coming season. 

[antipodes]

Mine are already going straight in the ground! usually they are very hardy but depends where you are...

[chriscross1966]

IT would have to be unusually savage for an onion set not to be perfectly safe if planted now....

chrisc

[Kleftiwallah]

I don't think it is mould,  I think it is mineral salts being leached upwards and onto the soil surface.   ???    Cheers,     Tony.

[tottieheed]

Thanks for your help. I think it is coming from the compost so I'm not too worried. The general thought seems to be that I could have them outside already. I will pop them in next weekend, whats the worst that could happen?

Thanks all once again, more questions to follow!

J

[JENIAN]

Had mine in the heated propagator in 3ins pots for last 3wks.  Now 4ins shoots so hardening off gradually.  Had the same white mould around some bulbs, which I removed, with no detriment to the bulbs.

[Robert_Brenchley]

Are you watering from the bottom? If so, it could be that water is moving up, bringing mineral salts with it, then drying out. The result is a salty layer on top. The answer is to water from above. Alternatively, if it is mould, you're probably keeping everything too wet.