I have an Emporer Lychee, still in the container with soil from Pine Island (looks like 5-1-1 with bark fines, etc).

Bad:

I did not give it enough water after it first arrived, and the edges turned brown. I've been watering it consistently ever since.

I used 9-6-6 Fish fert once so far this summer. I didnt think that would harm anything.

More Bad:

Despite the above, now a few weeks later, it suffers SERIOUS mega leaf-drop. (see pics). I have yet to repot, but now fear it will be more stress.

Factors:

-using tap water, 7.5 or so pH

-watering 1-2 times a week

-in greenhouse, temp never drops below 60 at night (80+ daytime)

-humidity easily over 80%

-gets maybe 4hrs sun a day if lucky

-fungas gnats and springtails abound in soil

-added Beneficial Nematodes to soil 2 weeks ago (kill gnat larvae)

-recently added epsom salts in water (last week)

-I discovered spider mites on other plants, so I sprayed the lychee a week ago just in case (neem oil)

-New growth seems to be fine, booming even!

Ever since the neem oil spray and epsom watering, leaves have been dropping in DROVES- though I believe that is only cooincidence. Something is seriously wrong.

NEW leaves are NOT dropping (yet) but I am noticing they are now showing tint of red.

Anyone have experience with this? Have a look at these pics.

Above: Left side is Lychee 4+ weeks ago, some brown on leaves due to not watering. Right side is today, new growth, BUT also notice older leaves are worse, and many GONE (bare areas of branches)

Above: Some leaves are not just brown on edges, but yellowing. Strange that the left and right leaves here are the same age, same branch, one is perfectly fine.

Above: DEATH. Brown leaves dropped a while ago over a longer period (past couple weeks), but the GREEN leaves you see here dropped just in the last 2-3 days!

It is perplexing to me to have flurashing growth and DEATH all at the same time. My only thoughts right now are that watering has been insufficient, or that the roots are not doing well (bugs?, nutrients?). And I thought Citrus was difficult... walk in the park compared to this. I like a good challenge, but dang.

Still waiting on my shipment of MycoStim and Exel LG Foliar Fertilizer.