Onions in pots - what compost?

Floss

I'm hoping to plant some onion sets, carrot seeds & garlic into pots, as we only have a small yard/ "courtyard garden".....

What compost do I buy? And can I use that for all the planting, or do I need to mix sand with it for the carrots?

Thanks,
Floss

floss2

Bump....I could do with the advice guys...?

knithryn

I have tried growing onions in pots and they were a disaster...so small that they were useless.Garlic hasn't fared much better.
Carrots however I have grown for two years now. The nicest compost I found was a growmore one. It felt really 'meaty', but I think in the first year I used growbag compost, or something else really cheap and they were fine. I used old recycling boxes (green deep plastic boxes for putting glass etc into) which we didn't need as we now have a big recycling bin. Root depth is important for carrots, so use the deepest tub you can find.
I didn't mix any sand with the compost for carrots because the tubs have enough holes for good drainage anyway.
I have also grown turnips with very good results.
This year I am trying parsnips (well if I can grow carrots surely parsnips will be OK), some Pixie cabbage, my leeks were a disaster, lettuce in the summer are fab, potatoes in tubs and even just in old compost bags were great (vivaldi potatoes are good - the butterless potato- taste buttery but less calories). Strawberries would be good in containers too...

a11waysindebt

You could start the onions and garlic in pots then transfer later. If you use the fibre pots you can transfer complete with soil to the space.

The only problem I find with garlic are the roots when grown in pots.

As for compost I normally add some sand anyway to any thing I grow.

I haven't done carrots for years but I used to use a sand/peat mixture.

goodwitch

I've grown onions, carrots, parsnips, lettuce, radish, runner beans, tomatoes, cucumber, marrow, chillies, spring onion, beetroot, cabbage and potatoes this year, all in buckets, plastic storage boxes and pots. I used ordinary compost with some chicken manure pellets mixed in a couple of weeks before planting. Everything grew well. I watered regularly and once a month gave everything some tomato feed. I haven't lost anything and everything has fruited prolifically. I have had carrots that were long and fat, some small onions but most were a decent size, good size beetroot, etc, etc. So long as you space out the onions and beetroot enough and plant your root veg in deep enough pots, most stuff grows as well as in the garden. I haven't had any problems with carrot fly and the weeds have been very easy to deal with because they don't get a big root in the pots. The only major problem I had was my cabbage being eaten away by caterpillars and butterflies.