Kev, many of us have learned things the hard way over the years. Good drainage is paramount in the world of container growing. Native soil should never be used...including a soil that you may think is "sandy". A good quality "potting mix" is what you want...if you are not making your own. "Moisture control" type potting mixes are not good (unless you are planting a hanging basket or the like)....that will dry out quickly. Keep in mind...trying to salvage a bad Non-draining mix by adding things like perlite, etc...is a losing proposition. A little trick I use (if I am lazy and don't want to make my custom mix) is add 1/3 cactus mix to my purchased quality potting mix. Hope this helps...