man WHAT A GARDEN .... !!!! thx for showing us ... this is one argument against a monoculture.... when one goes.. its like dominoes.... any interest in becoming enabled in mini conifers... we can fill up all those spots real fast .... pic below is a bunch of mini.. and small conifers surrounding my patio ... much more interest.. than a monoculture.. and as trees.. if you pick the right ones.. will NEVER need to be trimmed.... and will need absolutely NO CARE ..once established ... pop on over to that forum if you wish ken

I actually thought it was blight based on my google of pics and not mites. Cut and paste of their diag. I'll grab some more cuttings later when @ home. Diagnosis/recommendation: The boxwood sample submitted is negative for boxwood blight. The spots on the leaves are injury from boxwood leafminer. A factsheet on this pest can be found here: https://extension.umd.edu/hgic/boxwood-leafminer-shrubs  At this time of the year, the adults have already emerged from the foliage, have mated, and have laid their eggs inside new foliage. You can see that the new foliage is rippled and bumpy looking – these are eggs that have been laid and the larvae within has already started to feed. The best time for treatment is in early June, getting good coverage on the undersides of leaves. Apply the active ingredient acephate, carbaryl or malathion. Spinosad can also be used as an organic method. Damaged foliage can be pruned out. Since adults have already laid eggs in new foliage, the new foliage should be pruned out while the plant is still dormant very early next spring to help break the lifecycle of the insect. If not treated, boxwood leafminer can cause significant damage to your boxwoods. Since these are new plants, you will want to keep them watered throughout the summer and through the fall. Make sure the boxwoods go into the winter with enough water around their roots to bring them into the spring. When the ground freezes, plants are not able to pull up moisture, but they are still transpiring and losing moisture through their foliage. Ensuring good, deep irrigation

with all the alternatives out there .. and what you already know.. why are you still interested in boxwood??? i used to be so intrigued by all those castles or whatever .. ver-sales and british formal gardens .. etc .... and then one day the very bright light went on.. and i figured out.. i didnt have an army of gardeners to shear them .. they were a monoculture ... and no govmnt subsidy to pay for it all ... and so ended my fascination with boxwood ... ken

Not blight......just anemic-looking new growth. It should darken up as it matures. btw, 'Winter Gem' is one of the most blight resistant cultivars of box available, so unlikely (not impossible) for blight to be a concern.