Common causes of crispy leaf margins: Over-watering Too much fertilizer Under-watering Fluorine in water Using species as a guideline to whether plants prefer full sun or not is very helpful, but plants still vary greatly within species & the amount of sunlight any given plant will tolerate/prefer is genetically determined. It is, of course, best to acclimate plants to full sun slowly in most cases. This increases the amount of the pigment chlorophyll in green tissues & helps prevent sunscald. Chlorophyll is natures sunscreen for plants. If, after gradual exposure to full sun, the leaves appear bleached or whitish, it is an indication that the plant is not capable of producing enough chlorophyll to protect itself from full sun & it should be moved to a shadier location. Al

It is related to stress, but stress is a very broad term used to describe a plant that is operating at or very near the limits it was genetically programmed to deal with. The burned leaf tips or margins indicate the plant cannot move water to its distal parts fast enough to prevent those tissues from dying. The usual suspects are over-watering, which compromises root function and inhibits the plant's ability to move water, and a high level of salts in the soil, which can make it difficult for the plant to take up water. Often a combination of these factors combine to make it difficult for the plant to move water efficiently enough to prevent the burned tips/margins. Sometimes, plants are sensitive to elements/compounds in water, like fluorine or chlorine, but studies show that in most cases, these influences are taking the rap for something that more rightly belongs at the feet of one of the issues mentioned previously. The condition can be exacerbated by low humidity, but the way you can do the most good is by making sure you provide a healthy root environment. Soils that allow you to water properly and will stay well aerated even after you flush the soil are going to have the most significant impact on correcting the problem, just as poor soils that do NOT allow you to water properly are the most significant contributors. Raising the humidity around the plant, preferably in the whole room, is also very helpful. Misting will NOT make any evident contribution toward eliminating the problem. If you want to look deeper into ways that will allow you to water correctly, just ask. Adopting a healthy soil is the best way, but short of that, there are still other things that can be done to help ameliorate these unwanted symptoms. Al

I think it's just from change in enviroment. The light outside is much brighter and coming from more angles if they are out in the open. In the greenhouse they may have been shaded by other plants or the greenhouse frame itself. Did you have a shade cloth on the greenhouse? Even when plants are grown in a greenhouse they need to be gradually acclimented to outdoors. So, yes. Putting them in the shade or filtered light a week or so would help.

If you used a neem product with a label on it for plant application, there would have been a clear warning about not using it in the sun, or when temperatures are very hot. Most commercial Neem oil products contain 70% neem. I've never seen any directions that called for mixing it any stronger than about 2 tablespoons per gallon of water. It should never be mixed stronger than what the directions call for. Just as with other products (of almost ANY kind), more in not necessarily better. Your label will also state how long you should wait before reapplying your neem. It does not work like other chemicals which need to be reapplied after a rainfall. By the way, you must be cautious about spraying any chemical on your plants in the hot sun or very warm temperatures. Foliage or fruit burn is often a result. I'd be quite curious about the product you used and where (on line) you found those directions. If you tell us the manufacturer, we can look up a label and help you decipher it.