I plan to grow potatoes in a tall plastic garbage barrel this year. (The
barrel has a drain hole in the bottom and a series of 2-3 inch diameter
holes in its sides.) I was disappointed with last year's results so I
pose the following questions to the group:

Do I correctly assume that watering requirements are greater when
growing vertically like this? Is there some technique that helps retain
moisture for this type of planting?

As the plants grow, should I fill the barrel with more soil, or should I
use straw/leaves instead, or some layered combination thereof?

How much of the tops of the growing plants should I leave exposed as I
fill in, or do you just bury them completely as they grow?

How quickly should I fill in? IOW will the harvest be less if the stalks
are exposed to air and sun for more than some particular amount of time?

Thanks,

J.