I've started some cranberry and blueberry seeds I took from a frozen berries mix purchased at the supermarket last spring. About 90% of the cranberry seeds had sprouted around mid-June and only 3 blueberry seeds were germinated around mid-July.

Unfortunately, I have lost most of the cranberries due to strong winds exposure until I understood they need to be protected, since then they are all alive and I have 4 seedlings right now, only one of them seem to be perfectly OK, and it is the one I used to test half dose Ericaceous fertilizer effect on when the plants were about 1 inch tall, which seemed to be a good idea as its growth rate became obviously higher.

2 weeks after that I started fertilize all the plants but none of them seemed to react like the first one. I know those plants love sunlight, and recommendations I have read talks about half day of full sun, but I didn't know if they will tolerate direct sun in our extreme summer (average Max temp around 30c\85f and 19c\65f Min during July and August). most full sun - mild summer like plants don't thrive here under full direct sunlight so I gradually relocated them to a north shaded area that gets the 2 hours of direct sunlight before sunset that now in September has got shorten to about 45 minutes.
About 3 weeks after relocation some of the leaves became partially brown. As I wrote before - the only healthy plant out of those 4 is the one first fertilized, all kept at the same conditions besides that.
The blueberry is looking fine and grow slowly as I understand in should be.

All of them are planted in a commercial "garden mix soil" it is quite airy and able to contain a lot of water. The Ph is around 5 which seem to be compatible to those plants.

I find only a few pieces of information around the web about Cranberry and blueberry seedlings care and almost non about growing them in this climate.

After all that background, my questions are:

1. What can be the cause of the leaf damage? I find it hard to believe that the 2 weeks gap between the first fertilizations is the reason.

2. As you can see in the photo, the well growing cranberry (about 2.5 inch tall) starts tilting aside. Should I let it grow naturally or apply some support to keep it grow vertically?

3. I live in Jerusalem, 800m/2700ft above sea level which is around 32°N. As far as I know winter hardiness should be similar to US zone 9a, the Avg Min temp on January is 4°c/40°f, with a few days a year of snow/light frost but temperature rarely drops below -2°c/28°f. With a very limy soil around and tap water with the Ph of almost 8, I couldn't find anyone who had tried to grow those plants here, but I do know blueberries are grown in northern Israel at about the same elevation as here. Cherries grow here just fine and the total amount of "chill hours" required calculated for Prunus fruit trees is about 2000 per winter. What are usually the cold requirements of cranberries? Do they need dormancy only in order to flower and fruit or is it essential for keeping the plant alive the next season? If the second is the case, should I consider keeping them in the refrigerator for a few weeks during winter?
and what about the next winter? Should I keep them outside including the tiny blueberry or is it possible to keep them indoors and let them grow for a full year without winter?

4. soil: it is impossible to find peat moss around here, I have read that loam may be a good substitute for that but pure loam without sweetening lime in it is also unreachable.

I had a thought trying to make my one acidic compost but after a little research I found out that it doesn't matter how much pine needles/bark/coffee grounds I add to the compost, when fully decomposed it's going to have a higher Ph than loam or peat moss, and if not fully decomposed, it may have a low Ph but only temporarily, and is going to take precious nitrogen from the plant during the proses.

The only option I could find is making anaerobic compost which is similar to the decomposition peat moss and loam are going through. I haven't tried it yet but would love to hear about any subs for peat moss and loam that can keep those plants happy.

Thanks!

(the photo below is of the damaged leaf Crenberry)