Pro-Mix Questions

[Creeperpark]

If your soil is pulling away from the pots and water is running
down the sides your soil has become hydrophobic. If you use a
surfactant like dish soap at a rate of 1/4 tsp./4 gal as a wetting
agent, it will loosen the top layer. For the long run if you mix in
EWC/compost at 25% it will provide enough humus to keep your
soil from doing that. Well, that and a regular watering schedule
where the soil is never allowed to get severely dried.

hydrophobic soil can be bottom watered easily.