@gratefulredhead, please don't be afraid of watering to runoff. It is impossible to overwater by giving too much water at one session, such as watering to runoff... the soil can only hold so much water and then any extra simply falls out of the bottom drainage holes. The ONLY way to overwater is by watering too often, and your little drinks are doing that.
Water to runoff when you do water, and then leave them alone until they can drain that water. Do NOT give extra drinks. These are weeds... they need the adversity in order to thrive. Your kind little drinks are the problem. And, no, I was not talking about larger pots... these techniques are especially valid in the small starter sized cups that we use because this is the point where we are constricting the roots the most, and where we have the most influence on how fast they grow.
Stop thinking about the peat or plastic or even cloth containers being the key to this. The soil doesn't just dry out. Prove this by watering a container with no plant in it, just soil. See how long it takes that container to dry out... it can take weeks. You will prove to yourself that it is the plants that drain the water from the soil and how fast it happens has everything to do with the strength of the roots, not your local humidity or type of container or soil that you are in. Ok
@gratefulredhead, please don't be afraid of watering to runoff. It is impossible to overwater by giving too much water at one session, such as watering to runoff... the soil can only hold so much water and then any extra simply falls out of the bottom drainage holes. The ONLY way to overwater is by watering too often, and your little drinks are doing that.