I planted many native plants and shrubs last year. One shrub is a nanny berry and many of the new leaves are curling up. Some other leaves are blotchy and pale with green veins. All my other plants look healthy. The soil is very Sandy underneath a couple of inches of topsoil. We put compost in each hole as we planted last year.
We were wondering if the new leaves of her nannyberry could be eaten by aphids or thrips. Try checking under the leaves. You can try washing with insecticidal soap, both sides. The shrub will survive the insect cycle and put out new leaves. Viburnums of which nannyberry is a variety are susceptible to pests. Remember though that birds and other insect predators feed on these insects affecting the leaves and play an important role in the foodweb. If the plant is healthy it will survive. If her soil is very poor she may need to apply a compost mulch every year.
Another area that it could be is being abiotic, for example, root rot? Maybe something in the soil or compost.
The interveinal chlorosis could also be a sign of iron deficiency. Could be caused by the wrong soil pH for the plant to be able to pick up the iron. Soil testing would be a good idea. Or if the compost she used had high levels of phosphorus it could be making the iron chlorosis worse.
The curling of the leaves could also suggest potassium deficiency. Have a look at this article: https://www.independenttree.com/chlorosis/