water draining too fast - slow growth

You need to water the whole pot, not just a piddling amount next to the stem, roots will not grow into dry substrate and this could be why the growth may seem slow. It is far better to deep water until run off every few days than it is to give tiny amounts often. The soil could also be over dry and has become "hydrophobic", whereby water just runs through the pot rather than be absorbed. Standing the pots in a container of water for a few minutes and letting the water get sucked up from the bottom can rehydrate the soil quite easily and quickly. Growth could also be affected by keeping them in small pots too long, they really need 15-20 litre pots (or bigger) for best and fastest growth. Hope this helps, Organoman.