Right around the time I posted the 2014 review, I repotted my C. myrtifolia using a very deluxe brand of potting soil recommended by a nursery owner. Big mistake. The potting soil didn't drain well and the citrus tree developed root rot and started dying when it had 82 fruit on it. As the fruit and leaves dropped off over the course of a week, I managed to save a couple ripe fruit and planted the seeds. Some came true (citrus often helpfully clue you in to whether or not they've come true by producing two or more seedlings from a single seed). Other seeds from the same fruit yielded very different weedy-looking plants. My lesson: I now always make up a free-draining potting soil for my citrus. I typically start with a good grade potting soil (ProMix BX) and then add Turface (a baked clay product used on playing fields), and some fine pine bark mulch and/or chicken grit gravel. The ratio doesn't really matter that much as long as you use about 1 or 2 parts regular potting soil to 1 part comprised of the other ingredients.
I purchased a Myrtle Leaf orange from Logees back in 2009 right out of their greenhouse. The plant started off tiny--it was only about six inches tall--but growth was surprisingly quick--some new shoots grew two feet long in years two and three and had to be pruned back. Fruiting was a bit slow. It set one fruit in 2012 and three in 2013. This winter/spring/summer of 2014 it finally came into its own and has about 70 fruit on it (I counted 68, but may have missed a few) and is 39 inches high in a 15" diameter plastic pot. The fruit set either singly or in clusters near the tops of the longer upright branches. The small spacing between leaves and the small leaf size make the plant very decorative. A bit of pruning, and this citrus would make a fine bonsai as the Logees photo suggests but it looks great just lightly pruned too. Flowering occurred for me in January and then intermittently in bursts till the summer.