How short can I keep the hedge? Also, some shade and some sun areas.
Severe pruning of Boxwood, or keeping them very low can have mixed results.
My recommendation would be no shorter then 2 feet.
Here are a few links for you.
https://www.gardeningknowhow.com/ornamental/shrubs/boxwood/boxwood-care.htm
https://www.gardeningknowhow.com/ornamental/shrubs/boxwood/trimming-boxwood-bushes.htm
How can I help my boxwoods that are dying off in thatches annually? I have many boxwoods that were planted 16 years ago. Over the last few years, thatches of them turn bronze or dried up green, then pale blonde. I've been cutting the blonde bunches out, but the plants look awkward. Some have had so many pieces die off. I've had to dig them up. Is this just a case of extreme seasonal temperatures? What can I do? Is there another formal, small, evergreen shrub I can plant that will survive better?? Thank you!
Here is an article that explains the reasons for yellow or brown leaves on boxwood shrubs:
https://www.gardeningknowhow.com/ornamental/shrubs/boxwood/yellow-or-brown-boxwoods.htm
I tend to lean towards it being extreme seasonal temperatures. I, too, had this problem after the harsh winter we just had. There are steps you can take to winterize your boxwoods, which are discussed in the following article - i hope this helps:
http://www.detroitnews.com/story/life/home-garden/2014/10/16/boxwoods-need-winterizing/17381355/
Happy gardening!
Boxwoods tend to like shaded or partially shaded areas, so please check the location and the amount of sun/shade they receive. Another poster suggested winter burn, so please follow this person's recommendations. I would keep pruning the boxwoods, hoping new growth will occur to replace the lost branches.
Tree name?
Do you mean boxwood shrubs? If so, here is more info: https://www.gardeningknowhow.com/ornamental/shrubs/boxwood/boxwood-care.htm
I have newly planted green velvet plants that are being eaten. I thought they were deer resistant so could it be the rabbits?
Rabbits generally don't eat Boxwoods but if their food is scarce they may dine on your plants.
If the stems are torn and ripped off it is likely deer. If the branches are a clean cut, this is an indication of rabbits.
Are boxwoods trimmed in a square form sometimes? What is the proper way to trim Boxwood bushes?
This article will help with that: https://www.gardeningknowhow.com/ornamental/shrubs/boxwood/trimming-boxwood-bushes.htm
I have two large boxwoods. I would like to reduce the size down to half but when I trim too deep, I run into dry stems. Does this mean that my boxwoods are spent? Should they be replaced? They have gotten to wide for the area and are impeding walkways. I've had these since I bought the house in 2004. They have doubled in size since then. I appreciate any recommendations.
Regular pruning of Boxwoods makes for healthy plants.
I would avoid pruning the plants in the fall as they will not have time to recover and harden off before frost.
Instead wait until early spring to trim the plants back. Try to remove only 1/3 of the plant in the first pruning. Then go back in summer and remove another 1/3.
Remove any dead or diseased plant material anytime.
https://www.gardeningknowhow.com/ornamental/shrubs/boxwood/trimming-boxwood-bushes.htm
I am told a boxwood only last 10 to 12 years. Mine have been in ground 11 years and are losing leaves in patches, look like dieting stops?
A common time frame that greenhouses or garden centers will give for the life of shrubbery in a landscape is 10 years.
Boxwood can live and thrive in a garden for many years with good growing conditions and care.
Boxwood have shallow root systems and need good draining soil.
Cold and winter conditions can effect the Boxwoods lifespan, as well as disease and insects.
Pruning your Boxwood is as much a part of their care as watering.
Here are several links that will help you.
https://www.gardeningknowhow.com/ornamental/shrubs/boxwood/boxwood-care.htm
https://www.gardeningknowhow.com/ornamental/shrubs/boxwood/boxwood-winter-protection.htm
https://www.gardeningknowhow.com/ornamental/shrubs/boxwood/trimming-boxwood-bushes.htm