[bjp91]

I live in Central Florida. I have boxwoods around my patio that have probably been there 25 or more years. This year I've noticed that some of them are in decline, and some branches have actually died. Is this because of their age? I give them slow-release fertilizer twice a year and water them weekly, if we're not having routine rains. I've had moths from the sod web worms in them, but that has happened in previous years as well. They were allowed to grow a little taller than I really wanted them to be, but yearly I do trim them down maybe only 3-4 inches. The first two photos are examples of the decline; the last photo are of the 'newer' boxwoods, in that they may be only 20 years old (vs. 25+). They seem to be doing better. Any ideas? Thanks!

 

[agrostis]

https://www.google.com/search?q=bux....69i57j0l2.17677j0j4&sourceid=chrome&ie=UTF-8

According to this google search, buxus has a lifespan of several hundred years, you might have other problems. Those box look like they are planted mighty tight to the house. You are in FLA. Is it sandy where you are? Are those plants getting enough air, sun and water? There is boxwood blight to consider also.

 

[hort101]

https://www.google.com/search?q=bux....69i57j0l2.17677j0j4&sourceid=chrome&ie=UTF-8

According to this google search, buxus has a lifespan of several hundred years, you might have other problems. Those box look like they are planted mighty tight to the house. You are in FLA. Is it sandy where you are? Are those plants getting enough air, sun and water? There is boxwood blight to consider also.

And besides two different blights they get mites and leaf miners maybe more than 1 cause

 

[Smokindog]

I've had both fungus and white fly make boxwoods look like this. Hard to tell but that branch in the lower right of first picture looks like white fly. Malathion takes care of them but typically it also means too much moisture in the area. Otherwise I use a fungicide for roses (funginex). Either case, the recovery of the lost branches/foliage takes quite some time. YMMV

 

[bjp91]

The plants are in mostly sandy soil; admittedly, they have been allowed to grow too close to the patio/house and each other, but they do get ample sun and are watered weekly when it's not been raining out. They are watered from above (sprinklers, rain from eave overhang, and hand watering, etc.), which I understand, from what I've now read, is not ideal.

I also read up on boxwood pests and diseases - mind-boggling! Although many of these ailments end up with the leaves looking a lot alike, I'm going to guess my plants have blight. Rain and high humidity has been our norm this spring/summer, more so than prior years - which seems to be a big contributor to blight.

In the past I've had similar isolated spots on boxwoods in other parts of my yard, and I have always cut away the declining stems and the problem has, at least temporarily, gone away. But, the problem I am having in this particular section of boxwoods is much, much worse and I don't remember them looking anywhere near this bad last year.

From all that I read, if it is blight, these shrubs are 'goners'.

 

[agrostis]

If these boxwoods are important to you, then don't guess. You can find out exactly what the problem is for $40 in about 7 days. I highly recommend using this service.

http://plantpath.ifas.ufl.edu/extension/plant-diagnostic-center/

 

[hort101]

From all that I read, if it is blight, these shrubs are 'goners'.

There's two different ones one is treatable you'll need an expert or service like @agrostis suggestedThumbs Up
They'll identify the insect too
It looks like both fungal and insects imo but it's hard to be sure from pictures

 

[Patriot Services]

Biggest problem with Boxwoods is trying to keep them one size for life. They are meant to be majority .25 leaf bearing branches. Lco`s tend to keep shearing the leaves and allowing the branches to get too thick. Yours look like they need a year of no trimming, heavy feeding and then prune to a larger size. About 6-8 inches above the screen level. They always look scaly and fungal. That one brown spot was an insect but it appears isolated. Again insect infestation of Boxwoods is rare.

 

[bjp91]

They have been trimmed yearly because I don't want them any taller around the patio. May have to pull them out for that reason alone. I am thinking of taking samples to local county office for diagnosis (or, the above mentioned plant diagnostic center) - the only way I guess to find out for sure what is really wrong.

 

[hort101]

I am thinking of taking samples to local county office for diagnosis of the only way I guess to find out for sure what is really wrong.

That will work too Thumbs Up