The best time to repot your PL is in summer, when blooming is waning or stopped altogether. How large the pot can/should be is not dictated by the rote formula 'one size larger', but by the three-way relationship between plant size, container size, and the physical characteristics of the soil. If someone uses a blanket statement to suggest that you only pot up one size, without knowledge of all three factors, it speaks to a lack of understanding of the 3-way relationship mentioned. You can grow very, very small plants in very, very large pots if the soil is appropriate. We should also try to understand that no plant will "do well when it's pot-bound" if you are using a plant with plenty of room for its roots as a comparison. If plants did better growing under root-bound conditions, Mother Nature would have arranged for in situ plants to grow with their roots in tight little cones or cubes, yet we never see that occur. While it's true that we may be able to use the STRESS of our plants being root-bound to bend plants to our will and achieve OUR goals, the fact is that this serves US well, and not the plant. Growth - increase in biomass - is the measure of how "well" a plant is doing. Tight roots restrict growth and reduces the potential increase in mass, so even if we THINK plants are doing well because we use the stress of tight roots to get them to bloom or grow in a particular habit, the truth is they would rather have plenty of room for their roots to grow so they could grow as mother nature intended. No one is more aware of the negative influence tight roots has on growth than the bonsai practitioner who uses that tool extensively to bind down the plant's growth habits so the will of the grower, not the plant, prevails. Al

I haven't thinned them in a few years and didn't fertilize them last year. I went out the other day and they had some heavy string algea in the pot so I cleaned that all out and yesterday they looked a little better. After looking up some info I am going to repot them and add the tomato spikes I saw recommended. Thank you for replying.

Thats funny because I usually use Miracle Gro but got Scotts instead this time. Well I scooped out again. I went pretty deep Some of the top roots are now exposed. If it grows back again in the next few days (crossing fingers) I will go ahead and replant but I want to avoid that since I just repotted them a few months back and I don't want to shock the plants. Hopefully I got it all this time. I will just have to wait and see. Thanks

Not sure about changes in water quality, we are on town water and I have always used it for watering my Peace Lily. No recent house moves either and I just checked - we have both fluoride and chlorine added to the water supply. I switched potting mixes due to the aforementioned problem of yellowing leaves. Basically as a trial in a more open mix to determine whether or not I WAS over watering. I don't think I was, as all the roots were white and healthy (although rootbound). I'm debating whether or not to unpot the plant just to check the roots. But maybe I'll wait on that. I need to do a bit of research to determine whether or not I have her planted too low in the medium and if I have, I'm planning on replanting her in the correct position. I'll finish the watering experiment first though, just to rule that out.