The easiest thing I have found with schefflera is to mix A LOT of play sand into the organic topsoil. Topsoil alone holds WAY TOO MUCH water, it literally will drown your plants. The mix I have luck with is about 50/50 topsoil to playsand (I actually lean heavier to the playsand) and my schefflera are doing GREAT. I have pots that have a drain area on the bottom so I dont have rocks except on the top to keep chams from eating the soil. I actually am planting all my plants this way and seem to be having great success. And on an side note, the cham room smells like the beach! lol Good luck!