Big tubs... what veggies can I plant now?

Over the last 3 years I have accumulated 3 broken plastic 200 litre water butts... a combination of hard frosts and OH dropping a brick into one!

OH has cut them in half and I plan to use the top halves to plant stuff in... they're about a foot and a half tall and very wide.

They're sitting on the grass in front of my potting shed, they're open at the bottom so I was going to put carboard in the bottom, then some gravel for drainage, followed by a mixture of topsoil and multi-purpose compost... does this sound ok?

Next, what to plant? I was planning on peas, tatties (can I still get seed potatoes? If so, which ones are best to plant now?), and parsnips... any ideas on variety?

Does this sound ok? Have I missed the boat?

mini raised beds will grow anything you like really...but I don't think you need the gravel. They will drain easily anyway because they are raised

I do a similar thing for my pumpkins, and the roots escape to seek out water in the soil below

Too late for parsnips n tatties though I think

Get some "Alderman" peas. They grow upwards (6' +). Ideal for small areas.

Hi Diddy, personal choice I know, but I seldom buy seeds from garden centres, they charge too much unless they have a sale on.

I know you have your seeds now, but next time you are in the supermarket, Morrisons is a good one for seeds usually, or some of the el cheapo ones like Aldi and Lidl, Pounds shops etc.  See what they have for sale, much cheaper and I have found that most of the seeds do okay, unless of course you like more unusual varieties? 

Hmm... personally I would love to grow courgettes. Unfortunately, OH hates everything in that family of veggies... courgettes, marrows, cukes etc... it's soooo sad!