the so called lemonade tree is no doubt a marketing ploy. It's probably one of the 3 most common varieties, Eureka, Lisbon or Improved Meyer. Pink lemon is a Eureka lemon that has variegated leaves and will be pink when cut open but the juice is not pink, it's just regular ol' lemon juice color, dull yellow. If you are going to grow it in a container, Meyer is your best bet. for cooking Eureka or Lisbon are both similar in acidity, tartness and sweetness. Pink, while novel, tend not to produce quite as well in most areas. Ponderosa is a nice lemon, it is huge, so you have to watch your branches so that they don't break, and one piece of fruit is more than you need for most recipes, unless you are making lemonade, which takes a lot of juice. Most nurseries consider Ponderosa a novelty for it's size rather than a producer, although the fruit is good and juicy.

To answer the original question it seems as tho the plants are just super stressed, and when they get stressed they drop their leaves and fruit to survive. They are getting much different conditions than they were at HD, where they outside or inside a greenhouse in HD? I am going to guess that they were inside or at least shaded, they had to be hardened off in before just putting them in full sun. This is done by SLOWLY introducing them to the sun for a short period of time gradually working up to full day sunlight. Stop fertilizing and watering until you know for sure they are dried out. Than completely soak and repeat the cycle. Citrus will survive slightly dehydrated better than they will flooded. The meter you are using measures the electric conductivity of the soil so if it is littered with fertilizers you will get false readings. Are you able to post pics of the trees and their pots? I would suggest a re-potting and pruning, but as you said you are new to gardening and this may scare you a bit. Do you have any friends with a green thumb that could help you with this? Don't expect any flowers or fruits till next year as said since the plants are so stressed, but you never know with some TLC and luck you may get some winter blooms. Again pics would really help, and good luck!

Hard to say, since Meyer can flower nearly any time of the year, so we don't know when they started. Meyer fruit, when grown outdoors in Florida, can get quite a bit bigger than an average grocery store lemon -- sometimes up to grapefruit size, but commonly like a large orange. They will change from green to yellow as they mature, so that's the best signal that they're ready. Like all of the sour-fruited citrus, you certainly can use them earlier, while still quite green, but if you pick them too immature, there won't be much juice inside.

Sorry I could not get sooner to thank you all for posting so far, but I had some internet connection problems. All seems ok though now! Thanks for sharing all of your opinions and even pictures!!!! Thank you Mike for the congrats! This year is my first pretty good year getting fruit on most of my trees, some for the first time. I had given them a plant light last year, along with a new fertilizer I found this spring, and that seemed to help. I still need to get a better light for them now that they are inside. I started a post a month of so ago, and got a lot of helpful info from you all (thanks!). I am just deciding whether I am going to keep them upstairs in the living area where they have always been when I bring them in every winter, or transport them down to the basement. If I do basement, I would go HID, but if I stay upstairs, the HID would be too much, so I would just need something to supplement. Even the cheapy GE plant spot light I got last year helped well compared to just window light, so I am sure if I moved up to something a little better, I will be able to keep my leaves, flowers, and fruit attached for the whole winter season. ANyway, so I am finally getting good fruit to grow after all these years of waiting and learning how to keep them happy while indoors for the winter. (oh, and another MAJOR thing I learned from here that helped was how to make good REAL container mixes for citrus). Although I did not think of this before until mksmth said so and mksmth is right, that the flowers are all white so far. I will check again over the next few days as they get bigger. A few should open up soon. I guess the last test will be tasting it. But I feel so happy that the tree got fruit for the first time, that I am waiting till the last possible moment to pick them because I am enjoying just seeing them on the tree finally! I am also wondering what would be the correct thing to make with the first lemons. I would like to make something special with them just because they are special. Any suggestions? LOL! I will keep this updated as the blooms get bigger. THanks again for all of the help! Christy