Top dressing is common practice. But usually with dry amendments. Ewc. In conjunction with some sort of mulch. I wouldn't bury your plants to much with super soil. But that's just me. Kinda pointless. Stick with kelp, alfalfa, guanos crab mean ec ec. My top 2 inches of flowering pots are 1 inch Ewc. With dry amendments as needed. 1 inch mulch. I use equal parts perlite coir and compost. With diatomaceous earth. Crab meal. Neam meal. About 2tbsp / gallon of coir,perlite,compost. This controls bugs, keeps soil from drying out and top feeds a bit all at once.