The fading color, necrotic patches and marginal reddening of leaves is typical of sunburn. We had some very abrupt hot and sunny weather a few weeks ago. Recent transplants are susceptible to sunburn like this especially if they go from greenhouse or shade into direct sun. To prevent this in the future you can use a white shade cloth until the plants are adapted to the new conditions. For now, I think the growing points should be ok and there is nothing you can do other than take good care of them watering as needed this summer.