I'm not sure if my mom is correct in this, but we just transplanted 6 clumps of textilis gracilis bamboo (15' tall) from a nursery into 6 different pots. The bamboo is sitting in 15 gallon pots (with drain holes) and these 15 gallon pots are sitting inside of 20 gallon low profile pots (same height as the 15 gallon pots) but these 20 gallon pots have no holes. We are then filling the open space between the 15 gallon pot and 20 gallon pot with gravel. My mom said that there should be a few inches of water at the base of the 20 gallon pot and the bamboo which sits in the 15 gallon pot with drain holes will "wick" the water up to the roots.

I've read that clumping bamboo does not do well in any standing water. I was thinking that maybe I should put some drain holes along the 20 gallon pot, maybe 6-8 inches from the bottom of the pot so at least I know the entire plant won't be submerged under water in case someone leaves the drip system on too long or we get a rain storm. My mom said it's not necessary to drill any holes and the plant will do better in this condition. Can someone confirm if this is correct?

Also, it's been 3 days since we planted them and the leaves are very wilted (some look like they turned into needles) and many leaves are turning yellow/brown. I'm assuming this is part of the shock of cutting the large clump into smaller ones... but I really hope they make it.