Leaf reddening can occur with new growth, environmental stress, as well as with some infections, but in this case, the color blush just looks like either normal new growth or a normal response to either brighter light than the plant might have been growing in before it was planted or to another growing condition that it is adjusting to. Many plants have red pigments in their youngest leaves, since it acts a bit like a sunscreen while the leaf is maturing. (Rose foliage that emerges completely deep red is one extreme example of this phenomenon.) While some powdery mildew infections on dogwood foliage can also cause reddening, that does not appear to be the case here. How red leaves become can also be a genetic factor, unique to the individual plant. For now, the plant looks fine and shouldn't need intervention, but if symptoms change or worsen, feel free to send more photos.

Miri