What to do with black recycling boxes

There is almost no limit to what could be grown in redundant black recycling boxes, but I would like to make a few comments:

• The boxes would be very heavy once filled with compost so would need to be in situ before filling.
• They will need about 50 litres of compost.
• Ideally they will need some sort of watering system to ensure that they never dry out. Make regular checks to ensure that water is penetrating right to the bottom of the box. There are holes already in the bottom of the box to ensure the boxes aren't over watered.
• Plants will need regular feeding with liquid feed or should have about 400 grams of slow release fertilizer mixed in thoroughly before planting or sowing.
• Obviously with vegetables it makes sense to only grow crops that have a high value.
• It might help to paint the boxes white to keep plant roots a bit cooler in hot weather.
• Plant intensively but avoid overcrowding!