big city location ..

any extreme weather events.. like fires .. etc ...

it doesnt surprise me ... that they are not vigorous in that dark corner ... and it looks like they get no light from behind ... is there a wood fence behind?? .. in other words.. i dont think they all get the same light for some reason ....

dig some small holes after you run the water.. and INSURE all plants are getting proper water ... dont assume ...

bit vague on history .... when planted ... they were in stress the first year of planting.. was this the second season ...

its not uncommon.. even for evergreen plants.. to lose leaves in fall ... and with trees.. it might be related back to planting ... who knows ... how did you plant them.... etc ...

ken

Hello Ken thanks for your comments. I think you are probably right regarding the sun. It tends to be a little shaded in that corner vs the rest of the garden. There is a fence behind them which also blocks light.

When they were planted they were approx 4-5 feet tall. This was July 2018. The irrigation is working fine and all plants are getting water. I don’t remember the landscapers doing anything special with the planting. Just dug the holes and planted. No special soils or fertilizers.

We did have problems with white fly and thrips in the summer but that appears to have stopped since the season changes and it got a little cooler.

Again thanks so much for your comments.

My view is that that amount and kind of defoliation is not shading - that there is something else going on. Try doing a web search for "nitida leaf drop" and the like, seeing if anything comes up that appears to fit. If not, then try your nearest USDA Cooperative Extension branch office. Presumably they will be prepared to tell you on the phone what routine they want to use to be able identify your issue during COVID.

Tropical trees do shed their leaves. It can happen seasonally in some and could be aggravated by the shade of the fence. Planted you said they were 4 feet. They look to be 8 feet now and these are trees not bushes and packed in tight. Trees shedding lower branches is normal.

That is a lot of leaf drop though if it came on sudden, happened fast and for a tree that can be maintained as a hedge. Put on your best seeing eyeballs. Better, get a magnifying glass. Have a close look at the top and bottom of the leaves still on the ficus. Look for thrips, aphids or quite possibly spider mites. Plant sucking bugs can cause that kind of leaf drop.

Thanks for all the comments. Some updates....

The leaves are still swarming with tiny white flies (aphids?) and it does appear to me that the thrip problem we had in the summer has not completely gone away, although it is less obvious. The curling of new leaves and red spots on these leaves is still present in places.

On these pictures taken today, you can see that around half of the trees are losing green leaves, while the others are only dropping a small amount of brown. The green leaves are coming from the areas that have significant white fly and thrip signs so I’m assuming they are connected.

I have used Dead Bug Jack spray in the past on the the recommendation of the local garden center, but I’m not sure if there is a better or more suitable product?

Again, I appreciate all your insights and comments.

Thanks!

Hi Phil I am having the same problems with my Ficus Nitida trees.. I lost 2/3 of the trees in the last month.. My trees are about 2 years old.. and noticed that there were lots of whiteflies.. what did you do to get rid of them? did your tree grow back? Thanks to advise.