Hi, what you're probably seeing is an artificial moisture retention product that was in the soil in your pot. With all the rain and humidity, those little cubes of gel have filled themselves up with water. They won't do any harm, and you can just dig them into the soil if you want to be rid of them, or collect them up and throw them out. Plants sure don't need them here.
By the way, yes schefflera do grow well here but they also grow huge, and seed themselves very widely. They are considered an invasive pest plant here. If it is the dwarf variety, it's not invasive, but if it has the large leaves, you should make sure not to let it bloom - ever!
