Last grow I even drilled out the 2 liter seed starting pots I used as well as well the bigger 30L and 50L final pots, that small size I realized allowed a lot of moisture loss so next time I will water more often. When drilling out the pots I feel you really need to change your watering approach for that reason. The other thing is, I made a simple pot liner by stapling some breathable landscape fabric to allow the air/oxygen to come in and avoid the soil falling out the bigger holes. It must be a little tricky if you are drilling the pots out already filled with soil. I don't imagine that any roots that got chopped or nicked would be any problem as it would only be those on the that reached the sides of the pots.@Stunger I ended up drilling 1/2 holes about an inch apart near the bottom of each planter. I'm thinking of adding some smaller 1s a little further up. Just gotta do it soon cause don't want to damage roots. Should be good only week and half old in 5 to 7 gallon planters. Watering more Idc it's rainy now and maybe more work in a month but I want to be able to have dry spells and be able to feed em. If the soils always wet from rain doesn't help. It's easier to add water than take it away outdoors.
Here's some pics of what I did.