Posted: 24/12/2013 at 22:57
You can't grow many in a pot, leeks do need some space to produce a good harvest and economically speaking you won't get many for the effort, time and care you put in. Cabbage, cauliflower, turnip and swede are best not grown in pots and vegs which have a tappered root need deep soil to grow well.
Some vegs don't need much spacing to grow for instance spinach, chad, spring onions, radish, salad leaves, these have all grown well and produced good harvests for me in pots.
Some veg grows upwards for instance beans and peas, dwarf varieties do well in pots.
Then stuff like toms and chillies which produce their fruit above ground, depending on the variety can do well in pots. Some of the cherry tom varieties grow really well even in hanging baskets.
Herbs grow well in pots as one plant is usually sufficent for most families.
Hope this is helpful, I could go on but your Q was about leeks