I've never grown garden phlox before. This year I bought 2 Phlox Paniculata: Early Purple Eye, and David. Very healthy looking plants. Purple Eye was in bloom when I bought it. Planted them 5/30/19 in ProMix in a 60 quart planter, and fertilized with Osmocote Smart Release 14-14-14. Now I'm stumped with the new growth which seems very spindly -- see red ovals on attached pics. Doesn't even look like the same plant -- but it is Anybody know what's going on? I would appreciate any advice since I've never grown these plants before. Thanks!