We're getting ready for our 2nd year of planting our veggi garden on our roof-top.   
We learned a LOT the first year and hope that this next year's garden will be even better.   We composted kitchen scraps and all the plant matter from the garden; it's been turned daily and is ready to use.  A separate compost was started in December for next year.  As these are done in big rubbermaid bins, it seems not as good had it had more airation, but it's was the best alternative for our small space. 
We'll be rotating all the crops in our 9 boxes and changing up the plant companions this year.   Our three kinds of heirloom corn were planted too close last year, did not pollinate well and had an unknown pest that destroyed almost all our cobs.   Our butternut squash also had a problem with pollenation and creating fruit that started to form, but then went black at the end.  There seem to be more bees (and unfortunatley hornets as well), so between that and a little help from us this year (manual pollination), we hope that we'll have better crops.  
Lettuce and cabbage were successful, but a lot was lost to leaf eating catapilars - once we realized we had to look for them at night, the problem resolved itself.    
Istanbul's bright summer sun and very hot temperatures burnt our peas and many of the beans last year, so we're arranging for a bit of coverage for these crops.
Brocollini, which we planted at the wrong time (last spring) came up no issues, then had pests all summer (so did our Chinese cabbage), survived and has thrived throughout the winter feeding us nicely.   It's all in bloom now with lots of bees and we're hoping to collect some seeds for a FALL planting (duh!!).
Beets and carrots were stunted - VERY yummy and had no problem with germination, but they never grew past a certain size.  Not sure what the problem was there, but hoping with our compost mixed into the soil this year, we might be more successful.  
Tomatoes, potatos, parsley (still growing and being cut on a weekly basis), kale (2nd crop still giving), corriander (went to seed, which was collected for cooking and next planting), basil, rosemary, thyme, habinaro peppers, Turkish small peppers, nettle all did very well with no issues of pests.  

Planted chives twice and they never germinated - not sure if there was an issue with the seeds themselves or something else.  Will try again this year, but not hopeful.