Armando, I use whatever I have around. Most of these pots are probably <20% perlite with the rest being MG Potting Mix (the mulchy type) and BacctoLite. I usually add maybe 10% yard dirt in the mix (a shovel or two added to a half-wheelbarrow full). I mix in a wheelbarrow and premoisten until it just begins to clump. I hold off watering for a few days or week and just let it settle into the pre-moistened potting medium (something NC Pete mentioned which has been working for me). But after that, unless it's raining for days on end, an adolescent plant (4+ months old?) should be able to handle a good bit of water without too much worry.
Charles, Lemon (from Petals) is a bit of a mystery to me. It's doesn't appear to be the same as Marseilles and don't know if it is the same as either Latarulla or Dottato. It seems to be unique--maybe an old sport of one of these? (It has a clear meat, no strawberry tint, if that helps any. Leaves are HUGE with 5 lobes. Eye is not closed but fairly small.)The major production is on last year's growth so if you prune hard each year, your production suffers. Hence, my tendency to endure the legginess. It will fruit on new growth but not as readily as last years. I call this breba because I don't have another world for it. It's not a San Pedro because all fruit mature and is edible. I remember a recent thread that quoted EL's confusion over Desert King/Lattarula/Danny's Delight (white version). Maybe there is a connection? Petals once said it was Dr Welch's Lemon, which is probably S. Carolina Lemon. http://aggie-horticulture.tamu.edu/southerngarden/Figcitrus.html But there's also white and yellow Marseilles grown here, so maybe it's one of those. Or maybe not. It's confusing. What's certain is that it prefers production on the prior year's growth.