JWM, you had to pick a Meyer Lemon of all citrus to bring into a very warm home without direct sunlight, at least 10 hours of it...Don't be surprised if they all fall off and then the branches die back....I have to commend you od doing your homework, but I don't think you did it here(

You would of learned that the mix you are using is one of the worst you could use on citrus, especially if you are holding them indoors..

I would either find a very sunny spot as soon as possible of get those what I hope are very bright lights up asap..It is too late to change that mix out but you must be very careful not to keep that mix wet too long..Root rot can set up rapidly also causing leaf drop and a whole lot of pest issues...

If you want to do more research in to the best soil mix to use which I find most important, please let me know and I will guide you there..

They are so pretty right now, and I know you can keep them that way once you provide lots of light to compliment the very warm temps they are exposed too, or they will shed leaves and use a much better soil mix)

Welcome to the forums

Mike

You have probably made some of the classic Meyer
lemon errors. First, when you dramatically change the light conditions a Meyer
will drop most, if not all its leaves, to replace them later with leaves better
suited to the new light conditions. To move a Meyer from outside to inside
without the leaf loss, you need to move it from full sun to partial sun for 2
weeks; then to full shade for 2 weeks; then indoors; reverse the process when
putting it out in the Spring... and please DO put it out, if you can; you will
be rewarded with a happy, healthy plant.
Second, when you bring it indoors to a sunny window, the plant gets warm; but
the roots generally stay cool; and citrus roots don't like to grow into cool
soil... the solution is to put some sort of heater to warm the soil, or to put
the plant a little further from the window. The thing to remember is first the
roots grow; and then the leaves and branches.

Hobby,

They are all blue pots; but I don't see any indications that any of them are planted too deep.

One, maybe two have soil dug away from the trunk, presumably to expose the root crown that could be at soil level.

They're likely not getting near enough light. Don't forget--these grow outdoors all year in the sunbelt, including in the desert and thrive. They to replicate those conditions--lots of bright light (no way summer in PA was too much light, the sunburn you got was likely just because they weren't hardened off enough). Humidity really doesn't matter--stop spraying your plants when they're in the dark & cold, that just makes your rot problems worse.

What youre describing sounds like lack of light plus soggy soil. Considering your not going to have +110 F growing conditions, pot with a coarser mix in a larger pot, set up lots of bright lighting, stop with the misting, water less often, although water the limes more often than the others. Good luck!

Without reading anything..I can tell you just from the pics and your set up...Too warm of temps and very little sunlight to compensate......I hope you find a way to either cool them down or give them much much more sunlight...)

The roots are over working themselves in such warm house temps and dry air, and therefor shedding the leaves because there is no need for them if they can not take in sunlight to support root function...

Ha oops yes they are all blue. I meant the super close up one. I thought it looked a bit deeply planted.

Where did you get those coasters with wheels?

Hey all, thanks for the comments. I appreciate the insight. My wife bought the coasters from lowes. They work pretty well although I have to hold the pots while I move them. I bought the trees off of fastgrowingtrees.com. They have a lot of trees to choose from and immediately replaced the one lime tree when it showed up broken in the box. The top 10 inches or so broke off. The replacement was much more robust. So overall customer svc has been good. Regarding planting, I originally planted using compost only. Then I learned that they need potting mix that drains well. More research led me to perlite and vermiculite and desert sand so I bought all three and mixed together and replanted all of the trees. After doing so I learned the tops of the root base/root ball should be slightly above the soil. So I fixed some and the others that were close I just opened up the space right around the top of root base. Sooooo I have a new question now. Well several. I bought some cheap floor lamps and attachable grow lamps. I ordered some full daylight spectrum CFLs to put in the lamps and the grow lights I attached to the lamps (the grow lights came with full daylight spectrum incandescents). So I think the light issue will be taken care of but my question surrounds the amount of time they should get light. I'm not comfortable with leaving the lamps on during the day while no one is home so I bought some timers. My thought is to have them turn on around 5:30 or 6 pm right when I get home from work and then leave them on for 10 hours and then shut off in early morning around 4am. This begs the question though of do these plants need darkness? If I leave the curtains open all day (even though its a North NW window and light isn't good) and then hit them with 10 hours of unnatural light will it be too much or will they not get enough darkness? Under this scenario they would get no light from 4am to 6am. I can always keep the curtains closed during the day and thus they would get 10 (or 12 if need be) hours of unnatural daylight during "night time" hours. Any rhoughts? Does it matter? Lastly, I have good buds going on the Meyer lemon and large lime tree and am planning on self pollinating them. Do the buds need to be a certain size? I haven't seen anything about this just the basic "take pollen from the anthers and put on the stigma." I attached some photos. The first is of my larger lemon tree buds. The rest are of my Meyer lemon tree.

The photos. Typo. First pic is of my large lime tree buds. Second is of my light system. Waiting on the CFLs but once they arrive I will have four lights actually going. The third and fourth are my Meyer lemon showing the two buds and then some new ones at the top.

Vermiculite likes to break down fast, nothing to worry about right now. Consider just using perlite and another ingredient in the future. Compost, potting mix, peat if that's what you want.

there are other more advanced options you could learn about for the future too. 5-1-1 mix and my new favorite gritty mix.

Also they have these cool drywall anchors that you just screw in, with them you could hang those lights above the trees. It would be safer if safety is why your apprehensive about leaving the lights on when no one is home. No chance of falling over and starting a fire.

Light amount seems fine. 10 hours is a natural winter amount and the open windows in your northern climate likely aren't intense at all.

Pollenating? If you're still inside then, I'd just point a box fan at them and left the air do the job. You could try hand pollinating but that seems tedious, at least it would be to me. I wonder why yours are blooming--might be the stress they've been through? They should bloom Feb-March time frame. Some limes bloom year-around but won't set much fruit in the winter months, so don't be worried if the limes don't stick.

The size of the blossoms tell me that the trees are stressed..Not enough darkness at night for proper photosynthesis...Is there anyway you could put them on extending a few hours after natural day light at sundown, or putting them on before daylight, like before you get up?

Mike)