Posted: 26/06/2014 at 14:20
Q. 1 - They wouldn't grow very well in thin and dusty compost - that's why plants that are in containers long-term either need a soil-based John Innes type compost (which would be expensive in large amounts) or they need repotting with fresh compost - I would say annually.
Q 2 - Yes, that's what they would get if planted in a patch isn't it? If you were planting them in a veg garden you'd dig lots of organic matter (manure) into the soil and then plant.
My only concerns about your container are:
- I would put a few inches of coarse gravel in the bottom to aid drainage,
- I would worry about the metal of the container heating up and scorching the roots. Can you line it with some polystyrene packing sheets to protect the roots?