Different view:

First things first... the variegated Eureka is a rather weak cultivar, grown more for its "uniqueness" than for its production. Second, overwatering and underwatering have almost the same symptoms; the way to know the difference is to check the root zone.
Your tree appears to be a bit underfed, especially since it has to compete with your grass for nutrients. It is hard to believe how much food grass can steal from the tree; and citrus are infamously bad competitors.

Thanks John, That's good information.

This Variegated lemon is one of the first citrus tree I've planted. Had I known about the lack of quality of it's fruit, and now the vigor of the tree itself, I would not have purchased/planted it.

Looks like the most likely cause of my problem are "water" &/or "fertilization" issues.

My lawn has been place long before I planted the citrus trees (10+ years). I've been applying fertilizers (both granule and liquid) as recommended, same-oh-same to all my trees. There are about 15 more citrus trees of various varieties to the right and left of the Variegated Eureka. All trees are planted in similar ways on the perimeter of my lawn, and none of which seems to have this leaf shedding problem. So. It could be that this Variegated Eureka is not as vigorous a stock as the rest of citrus trees.

If the leaf shedding is caused by over watering, then this could account for the abnormal curling of the leaves. I'll monitor more closely with my moisture meter, and adjust my watering accordingly. Will post an update on the results.

Mahalo for your comments, Barry
FYI: I have 4 Improved Meyer lemon trees. They require very little maintenance. Great trees! Can't understand so many why so many people on forum having problems with them.

Gadget,

The Meyer has a somewhat well deserved reputation for being "finicky"; that is true in containers; but planted in the ground, it is quite easy to deal with; and planted in the field as a crop is almost a pet. Most people who have Meyers planted in the ground have great luck with them and almost no problems.

Almost two weeks has passed since my original post. So, just wanted to post an update on the subject lemon tree:

1. You will note by the attached photo, that the tree is now completely bare of leaves.

2. Been checking surrounding soil moisture content via moisture meter and by feel. Don't believe my problem is caused by either too much or lack of watering.

3. Also, don't think the problem is caused by lack of fertilization either. Mainly, because the adjacent citrus trees were fertilized in same manner, and they are doing great. See: Adjacent Honey mandarin and Moro orange trees in background.

Now, my dilemma is what should I do? Do I wait and see if the tree eventually dies, or maybe recover on its own? Or, should I try to dig the tree up and put in a container, so I can better try to nurse it back to health? Digging the tree up may cause more damage to the tree, then any possible care I can provide?

Any suggestions/comments would be greatly appreciated.

Thanks, Gadget

Remembering it is a weak cultivar; and maybe it is just dying, I would first pick off all the fruit; next prune out about 2/3 of the smallest limbs plus any crossing the center or growing in a downward direction. Lastly I would give it a good shot of citrus fert. applied at the dripline and watered in deeply. I would then start looking for a possible replacement tree; and hope this one recovers; if no recovery by Spring, take it out and replace with something else.

John,
Again, thank you very much, or as we say say in Hawaii,
Mahalo Nui Loa, Gadget

Native Hawaiian or Haoli? Punaho?
Oh, forgot to say good luck, even though I am no fan of the variegated lemon.

If it were mine I'd take it out and plant something in its place. It looks like it's gone to me. I'd plant a tango mandarine, gold nugget or satsuma in its place. Being in Hawaii I would think citrus trees are readily available at your Home Depot year round like they are for me in the SoCal desert. Just my 2 cents.
Evan

In looking at the pictures, It looks like there are basic issues on where and how the trees were planted. I'm also making some assumptions of the climate in HI, which might be right or wrong. I think you just finally had a problem from those issues. If the Variegated Eureka is a "weaker" cultivar, perhaps that helped it along.

First the tree is planted in or surrounded by grass. You rarely see citrus do well in that environment. I have seen some do OK for some time, even years, but they decline eventually. Several of the former groves trees around me have been killed when a house was built on the former grove and they planted grass around the trees. Virtually all of them have severely declined even if it has taken 10 years to see the damage.

Citrus need good drainage and if you are planting them, they prefer water to be able to drain away from the trunks. These seem to be planted at the bottom of a slope - or does the lawn area continue to slope down from the trees?

There are rings holding mulch around the trunks. I use rings around my big trees to keep mulch AWAY from the trunks and then mulch outside of that.

Perhaps it is a combination of those issues.

@GregBradley: Thanks.
Johnmerr made a similar point about my lawn possibly imposing harmful effect on my citrus trees. This is new info for me...Thanks.

FYI, I use the black rings to keep the grass away from the tree truck, and not to keep the mulch around the tree. The ring also acts as a bumper guard for my lawn mower:). Also, in the photo you may have noticed the gray PVC trunk guard around the base of the tree used to protect it from my weed wacker.

Now that I think back, several weeks before my Variegated lemon tree started to loose it's leaves, I did some heavy de-thatching on my lawn. After removing the thatch, I've been trying to bring the greenness of the lawn back with applications of lawn fertilizer (high nitrogen) every 3 weeks, and watering via sprinkler twice daily. In conjunction with the above, we've been had some heavy down pours caused by a passing hurricane.

So as you said, it's most likely a combo of those factors (water, drainage, fertilizer, weak cultivar) coming together wrong for the lemon tree.

Think I'll do as Johnmerr recommends, and see it shows any signs of coming back. If it don't, I'll replace it with something else. May even switch to planting a pomegranate tree.

Aloha, Gadget

Gadget,

You CAN have lawn grass and other competing plants along with citrus; it is just that citrus are very bad competitors for food and water, so you have to put a lot more fertilizer and a lot more attention. Here is a picture of one of my Antigua Meyers in one of 4 tropical gardens for which I am responsible.

The trees being in a mulch strip would make mowing easier because you wouldn't have to trim around each. And mulching should improve response from the trees, this is true in general whatever kind of tree (or shrub) they are. If you don't want to use organic mulch and watch it melt away rapidly under the tropical conditions then use rocks or other non-decomposing material - this will still shade the soil, improve the rooting environment (as long as it is not something suffocating, like solid plastic).

@Johmerr: Thanks, John. I hear what you're saying. The lawn in my yard plays an important role in my efforts in dealing with weeds and erosion. The citrus were planted to provide shading and ecstatics, along with the obvious benefits of providing great tasting fruits. I appreciate you posting this photo. It gives me confidence that, if done right, I can have both.

The Meyer lemon tree in you photo looks fantastic. Hopefully one day, my trees will look as good. I have several question wrt to the tree in the photo:

1. What's the height and age of the tree?

2. Your tree looks heavily laden with fruits. What type of fruit yield do you get from a tree like that?

3. Your tree looks like it's been pruned to keep it short. Is the tree naturally shirt, or did you prune the trees? If so, can you discuss and/or provide brief insight on how, why, when, and what criteria you use? (The reason I ask is I have another posting on this forum that ask this question on pruning a Satsuma tree.)

4. Can't tell from the photo. How do you keep the grass from congregating around the base of you tree trunk?

Aloha, Gadget

I thought it a bit more and decided that one of my area's problems with Citrus in a lawn may not apply to you.

I'm in inland hot/dry Southern California and having a lawn here means watering it every day in the Summer. The top few inches of soil just dry out too fast due to the hot sun and very low humidity. I think that contributes to the decline of Citrus in lawns. They don't like the constant watering and sprinklers getting their trunks wet.

I'm currently experimenting with some of the soil additives used by golf courses to help reduce water usage on my lawn.

Gadget,
1. 6 years old, 2 meters high. Carrizo rootstock (all my later 30,000 Meyers are on Macrophylla)
2. Last year 2 of these trees in this garden produced 900 lemons at 3 per pound.
3. Don't know about Satsumas; I am a one trick pony; no pruning necessary for the Meyer; it is naturally more of a bush than a tree. I do prune out anything including fruit that touches the ground; I prune out any downward growing branches (usually after I harvest the fruit); and I prune out branches that cross the center to allow more light to the middle.
4. I don't stress about the grass; but as I said, it does need a lot more food and care; and the tree needs deep watering, unlike the grass.

@Johnmerr, Wow! 900 lemons per tree. That's terrific. I'd be happy as a claim if I got 1/10th that in an on-year.

I posted a photo of my lemon tree, after giving pruning back. It maybe the last, don't look like it'll make it...branches seemed to be drying up. Will continue to provide fertilizer and water.

Thanks, Gadget

Good job; good luck.

Bummer and good luck Barry! Please update us - hopefully you will see some new growth soon.

I am going to chime in because I hate to hear the V.PinkL bashing; its one of my favorite fruits for cocktails and lemonade!

i agree that a fertilizer / water +/- issue may be the instigator of the leaf drop. Different rootstocks have definitely reacted differently for me - to soil, fertilizer and hydration.
BTW Any chance that the lawn fertilizer that you have used had weed killer in it?

Again - good luck. For me, the V.PinkL has been a very vigorous cultivar ...much more so the Meyers. Having said that, the issue that i battle is the freezes that i get during winter. My Meyers and V.PinkL in Napa spent the entire season recovering. The Meyer's branches all died by late August except for one fresh shoot above the graft line... latent freeze damage on the trunks. With my V.PinkL - the entire tree froze dead to within 2" of the graft line. The new (vertical) shoot is up over 6 1/2 feet now.

- George

George,

I use the Scott's Turf Builder fertilizer (w/o weed killer). It works best on my lawn (zoysia blue velvet grass).

Looks like you started putting in your citrus trees about the same time as me. I don't have 50 trees, but, I'm getting close. One unique problem that I have is purchasing and importing trees from our other islands, and the Mainland USA. We have a strict agriculture quarantine requirement that apply across the Hawaiian islands, and from the Mainland.

Another difference is that I have some varieties of citrus that appear to be very unique to this State (vice the other 49). Can't find much info on them online. Believe, some of which may have been developed at the U of Hawaii, others imported long ago from other areas. Believe they were targeted for our specific climate conditions.

Unlike you, I don't have to worry about my trees freezing over. I live about 400 feet above sea level, and the coldest it gets here is low 50's. I believe, similar applies to Johnmerr's Meyer lemon trees in Guatemala. As I'm located only a few degrees above his latitude, and both are between the equator and tropic of cancer:-).

Thanks for the well wishes, Barry