What source are you using for your water? It could just be calcium build up from hard water or it could be ...? could you describe where the tree is being kept and what sort of soil you are using, that sort of thing. Might help someone else make a more educated guess than mine.

I have the same issue with my vegetable garden, on one side I have an enormous lilac bush 15 feet away from the bed, on the other side fruit trees 15 feet away from a bed. When I planted them 17 years ago, they were twigs, and 15 feet looked like plenty of distance. Now, not so much. When you add all those good soil amendments, the invasive roots just love it and grow back pretty quickly. I use a pick to tear them up, going down 6 inches or so, then I don't bother to remove the small root bits, just plant in amongst them. What I've found is that the invasive roots suck up the moisture very quickly - IOW there are plenty of nutrients, the veggies I plant will grow just fine if I water them more frequently, like every 2 -3 days, instead of once a week that works for the rest of the garden.

I have noticed that one of the big problems many people seem to have with growing Gardenia as a houseplant is that it likes a steady amount of moisture but also seems to be sensitive to root rot if overwatered. My experience has been that plants with this sort of requirement often do well in hydroculture since hydroculture allows the roots access to ample water while also having a very well-draining medium that reduces the risk of rot. For those who have never heard of hydroculture, here is an example to show you how it works though I don't do things exactly like that tutorial. For example: 1. Instead of using a water gauge, I pot my hydroculture plants in clear plastic containers (such as deli containers or large plastic disposable cups) so I can visually see the water level. 2. I poke a hole (with scissors or such) in the side of the container at a level that allows a good amount of water to stay in the container at all times, but that allows me to easily drain out some water each time I add new water. I think it is important to flush the pot out with fresh water to avoid excessive mineral build up. 3. My experience has been that a mature soil-grown gardenia has a hard time adapting and will pout terribly (as gardenia pout at so many things), so I suggest starting CUTTINGS in the hydroton instead of plunking a mature gardenia in hydroton. If you start with cuttings, they develop roots that can live in the hydroton right from the very start rather than trying to nurse along a mature plant that has unsuitable roots until it grows new roots. The cutting I have seems to be doing pretty well so far for several months. It's not yet large enough to bloom, but since I know many people have had a hard time growing gardenia as a houseplant I thought some people might want to try this method. If you do try it, I will be interested to hear your results. Good luck!

It CAN matter, but usually doesn't matter all that much with houseplants. BA 3-in-1 contains a systemic fungicide (tebuconazole). If this gets into the soil, it's going to kill the soil-borne fungi. If part of the fungal population happens to be of the mycorrhizal variety and is in a symbiant relationship with the root system, up to 1/2 of the root system's ability to acquire water and nutrients can almost instantly go away. That can be a pretty hard hit. It's more likely to be an issue in outdoor plants during cool weather when mycorrhizal symbiosis is more likely to play a more significant role. I never see evidence of mycorrhizal hyphae in my indoor plants (even when they're outdoors), but I do see significant natural development of hyphae in almost all my temperate plantings in late fall through winter and into spring. Best luck, EHH! Al