Hello, blb88. Dried stems leftover from winter can be safely cut starting around mid June in your zone. If they have not leafed out by the end of June, they are not going to anytime soon.

Another thing you can do with these is to prune in very small increments of 1/4 to 1/2 inch until you reach bottom or you find green. The disadvantage is that you can accidentally prune flower buds. So instead of that, I generally wait until the end of May and then prune all of my leftover dried stems.

For people in northern states, waiting until the end of June is more appropriate. You are located half way up in the country so prune these dead dried stems between the middle to the end of June.

Keep an eye on soil moisture during this dry weather. A good way to do this manually is to insert a finger to a depth of 4 inches anywhere between the drip line and the base/crown. If the soil feels dry or almost dry then water deeply. If it feels moist, do not water. If it feels wet, determine why it is wet and take any necessary corrective measures. Also try to maintain three to four inches of mulch up to or past the drip line.

It is hard to tell what caused the lack of flowers. It may be due to pruning at an inappropriate time, lack of water or the weather:

* Macrophyllas that bloom on old wood should not be pruned starting in early August down here to September for the northern states. That is because flower buds for next spring are produced at that time.

* Once the flower buds are produced, they can die if the plant does not receive enough moisture so it is important to keep an eye on soil moisture between August thru blooming time in May/June.

* The weather can also kill flower buds if the temperatures get low enough or if the plant fails to go dormant and temperatures suddendly drop and stay down below freezing.

For more information on pruning hydrangeas and anything else about them, I recommend that you go to the link below. It has a lot of very useful information.

Good luck blb88, Luis.

Here is a link that might be useful: Pruning Hydrangeas

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