Back in the winter of 2015, a neighbor noted how poor my lime tree looked. She said her lemon tree didn’t have those “curly leaves” because she sprays it. A couple days later she brought over a blue bottle of the stuff she uses: Bayer Advanced — Fruit, Citrus and Vegetable Insect Control.
She was right. My lime tree did look ragged, its foliage sparse and damaged from having leafminers the first two years of its life. Citrus leafminers are the insects whose larvae eat zig-zag tracks, or mines, in leaves. The leaves become curled and unsightly after the leafminers exit and turn into tiny moths. The moths then lay eggs which hatch and eat mines through leaves again, and so on.
I’m leery of spraying though. I tried it once. More than a decade ago, I sprayed neem oil on a lemon tree because it was infested with aphids. The tree remained infested with aphids — until I took other measures to control the ants which were protecting the aphids from predators.
I’m not convinced of the effectiveness of many sprays, and although other sprays clearly kill target pests, there can be broad, long-term harm that outweighs short-term benefits.
But my lime tree looked so bad. It had yet to produce a single piece of fruit, and I began to think that spraying might be the only way to control these leafminers and keep the tree alive.
What’s in this blue bottle? Immediately, the active ingredient jumped out at me: imidacloprid. This chemical is the most widely used insecticide in the world. It has also had its use severely restricted by the European Commission starting in December 2013 due to its effect on honey bees.
Bayer CropScience, the developer and primary manufacturer of imidacloprid, both fought this decision by the European Commission and acknowledged the toxicity of the chemical to honey bees on the blue bottle I held in my hands. From the label: “This product is highly toxic to bees . . .” To reduce the risk of harm to bees, the label therefore recommends to “not apply until after trees have flowered or when bees are actively foraging.”
What happens is imidacloprid is taken into a tree’s system so that when a leafminer larva eats into a leaf it consumes some of the chemical and dies. But flowers are also part of the tree’s system, and when bees drink nectar from the tree’s flowers they also consume imidacloprid. They may not die, but there is sub-lethal harm all the same.
My lime tree wasn’t blooming at the time — this was February — but I knew that it was about to have its first bloom of the year. Then I read on the University of California’s Integrated Pest Management webpage for imidacloprid that the insecticide “can move into nectar, so don’t apply prior to bloom.” That was specifically referring to applying an imidacloprid product on the soil, however, not on the leaves. So I’m OK to spray now?
The UC IPM page continued, “Foliar application is not recommended because of negative impacts on natural enemies and bees.”
I was scared. It seemed that if I used imidacloprid, I would be harming both leafminers as well as leafminer enemies and bees.
I gave the blue bottle back to my neighbor.
More important than the health of my single lime tree was the health of the bees in my yard generally. My avocado trees and apricot and peach and orange trees were all about to start blooming too, not to mention all of my vegetables, and I needed these bees to help pollinate the whole yard.
In late February, the lime bloomed and it flushed new growth and it dropped many of its old and leafminer-damaged leaves, and here’s how its foliage looked in April of 2015:
To my surprise and delight, the foliage was as uniform and vibrant green as I could color with crayons.
There are no leafminers apparent anywhere. How could they have been so populous and damaging last year and now non-existent? And how could this have happened without my help?
Seasonal variation
One thing I’ve noticed over the years is that leafminer damage varies from season to season. When a citrus tree grows new leaves in the late winter and early spring, those leaves usually have little to no leafminer damage. Flushes of new growth in the summer tend to have the most leafminer damage.
This is how it occurs on my citrus trees in my yard, located twenty miles from the ocean in San Diego County. The pattern in your yard is probably similar. I’ve heard reports from others throughout Southern California whose patterns are similar.
So the fact that I didn’t have leafminers on my lime tree in the early spring of 2015 did not mean that leafminers were extinct in my yard. They have climatic preferences, just like we do.
Year-to-year and varietal variation
Sure enough, leafminers would appear again from time to time on that lime tree. Some years were worse than others, but the tree is a healthy and powerful producer of limes today. Here is how the tree looks here in August 2021:
Leafminers also damage some of my other citrus trees — although not equally. They seem to have varietal preferences. For example, here is my Valencia orange, on which I’ve only ever found a single leaf with a leafminer in it (I have no explanation for this):
Natural enemies
Why haven’t leafminers increased their population and caused even more damage to the leaves of my citrus? I have a good amount of food for them, with nine citrus trees.
The UC IPM webpage about citrus leafminers says, “the best course of action is to leave it alone and let the natural enemies of the citrus leafminer feed on and parasitize the larvae in the mines, rather than trying to control this pest with insecticides.”
Natural enemies? These include tiny wasps such as Cirrospilus and Pnigalio species. The UC IPM webpage goes on to explain that they “lay their eggs inside the mine, inside or on top of the leafminer larva. When the parasite egg hatches, the parasite larva consumes the leafminer larva.”
UC IPM: “In other areas of the world where the citrus leafminer invasion is long established, the experience has been similar: a high level of damage to citrus in the first year or two is followed by decreasing severity due to natural enemies parasitizing or consuming leafminers. These natural enemies, which are already present in the environment, survive by seeking out mining insects in which to lay their eggs. Eventually, the leafminer populations decline as the population of natural enemies increases.”
Therefore, my conclusion: Don’t spray and the bees won’t be harmed and the natural enemies of the leafminer won’t be harmed and will be able to do their work. Their work, however, is not to exterminate their food source (leafminers). So we will have to tolerate some zig-zag tracks and curled leaves.
Not a real problem. We’re growing citrus fruit, right?
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Thanks for the info. I planted 3 citrus trees last spring (Bearss Lime, Ruby Red Grapefruit, Eureka Lemon). My lime took off and was attacked by the leafminers. I was sold on using this product from the Orange County Rare Fruit Growers Website (http://www.ocfruit.com/files/LeafMiner_Psyllid.pdf) and was going to do so in February for all my citrus but after reading this I’ll just let them go as you did and hopefully they will get healthier with time.
I have been spraying neem oil on all of my trees (4 Avocado and 3 Citrus) periodically. Should I continue to do so or would this kill off the good predatory insects along with the bad ones?
I also have a worm farm and brew worm tea with the castings every now and then. I foliar spray all my trees with the tea. What are your thoughts on using worm tea?
Thanks for the help…
Eric,
I think it’s a good idea to leave your citrus alone and see what happens. Here is an update on the citrus in my yard (December 2017), where I’ve still never sprayed anything: Two trees (Gold Nugget mandarin and Valencia orange) have zero leafminer damage while the other six trees have a little. Most importantly, all of the trees are producing as much fruit as I could expect for them at their respective sizes. So I’m still satisfied in having a few ugly leaves on most of my trees.
(By the way, the Bayer product in the article you linked to is the same as the one I wrote about above.)
Neem is like every other pesticide that I know of, in that it can have at least some effect on “good” bugs too. For example, according to the University of California Integrated Pest Management webpage on neem, it has some toxicity to bees, particularly if it’s sprayed at the wrong time of day (http://ipm.ucanr.edu/TOOLS/PNAI/pnaishow.php?id=53). There’s no free lunch, I guess.
I’ve never used worm tea in any way, including as a foliar spray. Seems like it should be a helpful thing though, but I don’t know. I have a book called “The Holistic Orchard” by a guy named Michael Phillips, and he talks a lot about making teas and spraying it on the leaves of his trees. My impression is that it’s a lot of work, and so, assuming there are some good results, are the results worth the effort? Phillips also talks about the challenge in getting teas to have the right balance of microbes. Might be easier and still plenty beneficial to just use the worm castings without brewing tea. But I’m just speculating. Again, I have no experience with it. Have you noticed any results from your worm tea sprays?
I just started getting into gardening within the last year so I’ll continue to brew some worm tea every now and then and I’ll let you know how it goes. You are correct in that brewing tea is a pain but my kids get a kick out of it so its cheap entertainment (Like you I have two boys ages 3 & 1)
Thanks for the advice on neem, I thought that would be the least harmful to the environment and the last thing I want to do is hurt bees.
An unrelated question. This spring I was going to take down some Italian Cypress and put in a trellace with passion fruit. Do you have any experience growing passion fruit? I was at a nursery in Fallbrook last spring where I tasted some and they were delicious and the flowers were beautiful…
I’ve been thinking of doing a post about passion fruit for a long time. Your question makes me think I need to get it done. I have two favorite edible vines: grapes and passion fruit. If I want it evergreen, I go with passion fruit; if I want it deciduous, I go with grapes.
I have grown quite a few passion fruit vines, and I think I’ve tried about four varieties. I’ll write a full post about my experiences very soon, but I’ll just say now that passion fruit will climb a trellis very well, make sure you don’t mind its shade in the winter too, passion fruit grow fast and strong though you can prune them back, and they’re nicely clean since their fruit drop to the ground when ready or near ready to eat but don’t split open and make a mess. And your boys should love them. Mine sure do.
Looking forward to your passionfruit post, G. I just bought my first—the label on the nursery pot says Passiflora Edulis Purple Granadilla, which seems generic, but the nursery told me it is an edible purple variety, so, fingers crossed. I am building a 4 foot x 50 ft trellis fence for it to hide a less than desirable view of a propane tank, but also so the fruit is easy to reach. I love those beautiful other-worldly flowers!
I’ve had citrus trees for over 20 years and have never sprayed them with anything. This year I did put a little IV organic sun protection on it, but that’s it. the only thing I do besides irrigate them via a ring of 1/2” drip tubing and fertilize occasionally with an organic citrus fertilizer, is to clean up all the fruit that falls on the ground, and keep a thick layer of mulch around it—away from the trunk.
I love how you’ve pruned your orange tree!
Hi Teri,
Have you seen this post on passion fruit? https://gregalder.com/yardposts/passion-fruit-best-edible-evergreen-vine/
Yes, Greg, I have read it–excellent! Prepping my planting area for a new “Frederick” and the other purple variety I bought before! they’ll grow on a 50′ chain link fence, hide my propane tank and a less-than-desirable street view, while still being easily accessible to pick the fruit!
Sounds like a perfect situation for everyone!
Would love a piece on passion vine. I just in the last week had a massive die back of my vines. They have been fine all summer and then….crash! As for spraying citrus for insects, I would never. I really love swallowtail butterflies and their “bird poop” caterpillars!
Hi Tanya,
Sorry to hear about your passion fruit vine. Is it more than a handful of years old? Here is my post on passion fruit vines: https://gregalder.com/yardposts/passion-fruit-best-edible-evergreen-vine/
I also love the bird poop caterpillars. I photographed one just the other day.
Everything I plant here in Fillmore seems to limp along, except the italian cypress trees, pomegranates, and the passionfruit. The former were planted well, by farmhands. The passionfruit was planted by me, but in a spot that gets water. We are very stingy with water at our house, so the avos limp, the limes limp, the lemons stagger, the oranges seem to be doing ok. But the passionfruit was planted on a shared fence downhill from some irrigation so it’s getting our water and some from my neighbor. We don’t eat them bc they are quite a bit of fuss. If I knew a quick way to de-seed and process the pulp, I’d freeze it for spouse’s smoothies.
Thank you everyone all of this comments are really full of great ideas on how to keep those pesky leaf miners off our citrus trees, which are only two, but it is a constant struggle to keep them healthy looking and growing in their first three years since we planted them.
Just today I cleaned them off of all the leaves with that whitish, powdery infestation.
So, no spraying and instead let the larvae enemies feast on them and hopefully we get some mandarin oranges and limes soon. The peach we have looks great, but we have to protect it from the frost.
Best.
I’ve been enjoying reading your conversation and of course before that the post thank you very much to both of you!!!
I do have a lemon tree and a lime and two are a small city street but no idea what they are some battling some diseases and I’m learning a lot about them… I feel like it’s a lot of work at least for me a woman!
I have a grapevine! That’s beautiful and Has extended about 225 feet! It’s Grand the word that comes to mine right now .. What do you do with your grapevine when you have raccoons coming in at night time to satisfy themselves? I tried to protect the property from them with fences and other method. Good. They entered The property over 8 foot fence, climbing a tree and climbing over the roof and on the other side, they literally just climb a tree and walked the 6 foot block fence all the way to the grapevine… I’m three weeks away from them arriving and I’m terrified before Covid. I literally spend about a month every night Guarding the property of the holes in a powerful light..
If they arrive and I will not eat, I’m in disgusted…
I believe Two years before that I tried to remove the grapevine so much anger and I couldn’t kill it actually came back and my father wasn’t here because he has plans with his grapevine and it’s such a special Gravine to us…
My grandfather on my father side has brought this little stick baby of this grapevine). in his Luggage from Romania!!!! 🇷🇴 For his best friend which lived in Fullerton at a time.. And he actually removed it from my grandfathers on mother side grapevine (Which was a famous Vineyard and Transylvania… idk name of the grapes (now I will put some
Interest in this garden after reading this post! w all citrus.. in new to all gardening!.. and the grapes are sweet and delicious!! grapevine makes so manny! I gave out to most people I know in Yorba Linda from neighbors to mail man to water guy, gas meter reader and so on!!). Anyhow.. I pulled it out but not enough apparently.. and grew back… now as I was reading the post and blog I was watering it… it’s beautiful 😍 ..
So question.. 🙋♀️ what should I do about raccoons?!🦝
And any of you tried covering the citrus trees truck w lime (white powder mix water) ?!? That used to be done back in the old days in my country to all the trees doing the month of August to Keep pests away
Any thoughts on that? Anyone tried it?
Would that harm citrus trees?
Greg, so glad I found your website. We have Meyers lemon planted in the ground that is about 14 yrs old and has stayed toddler height with about a 4 ft wide crown. It has always produced a large and lengthy harvest. Starting last fall it begun losing leaves, some green and some yellow. I refined our watering system and schedule to be fewer but longer duration and still the thinning continued. Many of the legacy branches are dead looking while this year’s new shoots drop their few leaves after setting buds.
I grew very concerned that the remaining lemons from last season, which we customarily leave on tree until needed, were sapping the trees growth energy. Sorry but I picked the remaining 3 dozen fruit today. I then found your site and read up on all things citrus thinking I’d be pruning and spraying for pests. I now know not to do either. I last used only Neems oil before being alarmed by the impact to bees. We are on a coastal onshore hillside in Encinitas
Please send me an email as I would like to send you some photos of the poor thing.
Regards, Barry
Hi Barry,
Sorry about your tree. The decline of a mature citrus tree can be caused by many factors, often compound, but please send photos and I’ll do my best at remote diagnosis.
The same thing happened to me with a 20 year old Thornless Mexican lime tree this past February. It was growing right next to a Meyer Lemon and a Moro Blood oranges, bearing fruit like crazy, and within a month it dropped its leaves, set buds, buds died, tree died. Heartbreaking. I had fruit tree specialists from Fruitstitute examine it, including the roots, and they couldn’t determine any pests, fungus or any other cause of the tree’s demise, attributing it to old age. Some say semi-dwarf and dwarf trees don’t live as long as standard size fruit trees, but I’m not sure this is true. In any case, I prefer semi-dwarf trees for ease of picking fruit. I grow about a dozen different citrus trees, all about the same age as the Thornless Mexican lime I lost, and I’ve never had to treat them for any issues.
I’ve read that here in S. Calif CLM (citrus leaf miner) moths don’t usually appear in the early spring. I start getting them in June/July, just when I’m starting to think it’ll be a CLM free year. They increase into August, September. As you probably know, they lay their eggs on new leaves, before the leaves harden off. This can occur when the new leaves are only 1/4″ long.
This year I’ve been spraying ultra-fine oil on the flushes of new leaves, the moths don’t like to lay their eggs on the oily underside of the leaf. That seemed to work, but I didn’t follow up enough times and in the last month I’ve been finding a lot of mines on the new leaves. I’m doing two things to stop them: when I come home at night I go out with a bright flashlight and when I see mines I will look for the worm/larva itself and rub it off. The mines usually start near the center axis of the leaf and near the beginning of the leaf. They wander around for weeks and end up near the edge of the leaf…and that’s where you can easily spot the small worm/larva. Later, the 4th or 5th instar, they will roll up the edge of the leaf. So you see a young leaf with a small part of the leaf’s edge rolled over, just squish it gently.
The other thing I’m trying is when I see a new flush of leaves, I put 5 gal paint strainer mesh bags over the branch with the new flush and cinch them tight around the bottom of the bag(I use clothspins). Then I leave the mesh bag(s) on until the leaves have toughened up, about 2-4 weeks. Sometimes the weight of the mesh bag will keep the new leaves from growing straight up but there are ways to deal with this.
This ideas work because I have a lot of young citrus in containers. It would be harder to implement them on a large tree, though your bearss lime tree looks small enough.
BTW, I like the idea that their presence tapers off after a few years, but I haven’t seen that happen yet here. I’ve been reading about home breeding the parasitic wasps…they are expensive to buy from the commercial suppliers.
Hi John,
Thanks for sharing that. I haven’t paid close attention lately to when certain citrus trees in my yard are getting leafminer damage, but it seems intermittent and unpredictable.
This year, for example, the early flush on my lime had no leafminers, but the midsummer flush had some. Other nearby citrus trees were sometimes damaged by leafminers and sometimes none were present. These are adjacent trees. I can’t find a clear pattern. I’ll try to pay closer attention next year.
Overall, however, the level of leafminer damage on all of my citrus trees is pretty low and acceptable to me. Maybe that says as much about my standards as anything else though.
Greg, you won’t see leafminers in May. They start around June and get more and more vicious into Sept. I have lots of citrus and I live on a hillside. I think the Westerly winds bring the leafminer moths up the hillside to feast on my trees. I tried not doing anything and it was a disaster. I began spraying with Spinosad and now mix it with an oil spray to make it last longer. I also buy leafminer traps from Amazon that have a bait that attracts the male moths into a glue trap. I see the thousands of them in those traps at the end of the season. You might have lucked out with the parasitic wasps, but I don’t think I have enough, if any, leafminer predators in my area. BTW, I just started going through your website and you have one of the best on the web. I really like your dedication and honest articles along with your writing style – exceptional!
Hi Richard,
Thank you very much for the kind words! And thanks for calling my attention to this post on citrus leafminers. It was written almost three years ago now, and I haven’t revisited it lately. I see, however, that I left the impression that my lime tree no longer gets any leafminer damage, which is not the case. Some flushes of new growth get attacked, some don’t.
I have a dozen citrus trees and the leafminers only ever attack certain varieties. Some they have never attacked, for whatever reason. Also, some years or seasons get damaged much more than others. Anyway, the leafminers are still around although their damage is tolerable by my standards. I don’t see any reduction in fruit.
I’ll take a current photo of that lime tree, add it to the post above, and update the information. Thanks for pointing it out.
Hi,
this is Nasir from Bangladesh. i would like to know about the farming guideline of Mango and Lemon….
Hi Nasir,
If you’ll be growing these in Bangladesh, then I’m sure I’m not qualified to advise as the climate their is unfamiliar to me. I’m sorry.
It’s October 30th and I couldn’t stand seeing the huge numbers of 8-foot long suckers and leaf miner damage on the tips of the center branches of my Eureka Lemon (which is about 5 years old), so I cut them out yesterday. Now, after finding your site, I’m feeling very bad about it. In the Central Valley (100 miles from SF and Sacramento), the frost will be coming soon and I believe this will be a cold winter. This particular lemon tree has only produced about 6 lemons since it was planted (south side of house north of short stone wall). Another mistake I made (after pruning a nectarine and an apricot) was to clean out the center crossing branches. What would you recommend to help with the disaster I may have created…? The tree is otherwise growing vigorously (Thank God!). Will I need to wrap it to protect it from either sunburn or frost damage?
Hi Linda,
I don’t think you’ve created a disaster. I understand wanting to cut off those branches with leafminer damage. Lemons are vigorous, as you noted, and the tree will probably be just fine. At this time of year, it’s unlikely you’ll need to worry about sunburn and if nights haven’t hurt the tree in past winters then I wouldn’t worry about it.
Linda, Paint exposed branches with 1:1 white latex and water. To protect the thin bark from sun bleaching.
Thank you for your insight; I have leaf miners on some, but not all, of my trees. We do mulch heavily and I am going to follow your lead – no spraying.
New to this great site. here in coastal of, i only have the leaf miner problem during the second summer flush. First flush is fine. spraying spinosid is effective but you cant stop, spraying religiously every 7-10 days. Now that the trees are big. The few leaves attacked, I just remove.
Hi Greg, I really like your website. Lot of good information from you and people who comment. Lot to learn.
I have a question about my mexican keylime tree. It has been 5 years in the ground, not produced a single fruit other than the first year. The leaves are all curled with the exception of a few. Suspecting drainage issues for the stunted growth, I dug it up 2 years ago and replanted with cactus palm mixture. I fertilized it with special citrus fertilizer, watered it well, even added worm castings and all in hope to revive it. After being in shock for a couple of months the leaves came back but the growth again stayed the same as before and the leaves curled up. I dont understand what I am doing wrong. Is there any way to tell what could be wrong? I am thinking of giving up and planting a khishu mandarin instead. BTW, latest I have cut back on watering as I got some advise from San Diego master gardeners that I may be overwatering which can cause root damage.
Let me know what you think and if you need pictures, I can provide those.
Hi Avi,
Sorry to hear about your lime. Lots of things could be happening. Open up the curling leaves to see if there are insects hiding inside. If so, identify them. Often, it’s aphids or cottony cushion scale. It might also be leafminers. Regardless, none of these pests usually significantly stunts a tree.
It’s not a great idea to add anything except your native dirt to the hole you plant a tree in. If the drainage is bad, plant on a mound. Tree roots don’t like when there’s an abrupt change in soil type, which is what you create when you add a bunch of stuff to the planting hole. So you might find that the tree is not rooting outside of the cactus palm mixture that you added.
But maybe it’s something else entirely. Sometimes potted trees are rootbound when you buy them and they will always be stunted, as the roots circle and girdle themselves, and it’s not your fault. I’ve planted a couple citrus trees like this. Ultimately, I’ve removed and replaced those trees. Don’t waste more time on this tree if you suspect this is the problem.
Thank you for all the information on citrus trees. I found out so much more than what I searched for. I was just worried about some curled leaves now I want to plant more trees. I love all the info.
Hi Kim,
That’s great feedback. Thanks! Wish you luck if you plant some new trees.
Sadly I will spray for the leaf minors, it has been three years with no spraying and they literally are just about killing all new growth. I live in Georgia and I think some came in inside leaves, and they have no natural enemies here.
Sorry to hear this, Glenn. Wondering if in Georgia you find that the worst damage is in the later part of summer whereas the new leaves in spring are often not attacked at all? This is how it usually works around here.
Hi Greg! I have a Persian lime tree that I have some problems with. First and foremost it doesn’t produce much fruit. Plenty of blooms, but they just don’t blossom into fruit. On the rare occasion one does produce, the fruit has a strange flavor. I have not applied any sprays at all once I see a flower starting to develop, and a light mixture of neem oil w/ soap is all that I’ve used. I do fertilize about once every 3-6 months w/ a citrus fertilizer. I did notice ants on the tree around the flowers and suspected they were cutting them off. Non-adhesive tape around the base w/ some sticky glue on that solved that problem. I’ve had some pretty severe leaf miners around this tree as well. I’m in western central Florida. My biggest concern is the taste of the lime. Thanks!
Hi David,
Just to make sure, have you considered the possibility that rootstock has overtaken your lime scion: https://gregalder.com/yardposts/beware-of-rootstock-suckers-on-citrus-trees/
Hi Greg! I love your site and really appreciate all your thoughtful articles.
I have a citrus tree (I think maybe mandarin) that has white rings on the fruit. I’m wondering if you can tell me what it is and if I should be concerned. Is the fruit okay to eat?
Hi Jennifer,
Thank you! I’m not sure about that. See if your fruit look like any on this page: http://ipm.ucanr.edu/PMG/C107/m107bpfruitdis.html
That is a great resource, thank you! Unfortunately nothing looks like what I’m seeing. I tried to send you a picture but WordPress rejected my email ?
Thank you for making gardening easier by advising us to let the natural predators take care of the leafminer problem. My citrus trees get attacked too but I don’t want to use chemicals that could harm bees. Apparently the bees realize this and an entire swarm visited our orchard. Luckily, a neighbor is a bee keeper and took them home with him.
On a different note, I asked for your recommendation for an orchard manager for a new neighbor. You asked how many trees and what type. Answer: approximately 200 naval orange trees and 80 Haas avocado trees. He wants someone who will tend to the trees and harvest them.
Many thanks,
Lorie
Hi Lorie,
That’s a great sign that the bees find your yard so hospitable! I’ll contact you about an orchard manager recommendation.
Hi Greg, just found your website! Lots of great info. My question is how do I know if I am over watering my citrus or not watering enough? I use a moisture meter but I am not sure how accurate they are. My lime trees leaves look like they have an iron problem but I do feed them so am wondering if I am watering too much.
Thanks, Robin
Orange, CA
Hi Robin,
Citrus leaves roll up into a taco shell shape when the tree is thirsty. Citrus are tough in a location like Orange. You can test how much water your particular tree needs by letting it show thirst through its cupping leaves, and then watering it. Do that a couple times to get a sense of its watering needs and then you might gain a better idea of whether you have been watering too much.
See this post for photos of thirsty citrus leaves: https://gregalder.com/yardposts/reading-citrus-leaves/
Thanks Greg! Appreciate the info.
I used a winter soak of spinosad on my improved meyer lemon tress, and used nematodes
a couple of time, and I no longer have those problems. It had spread all over the yard, and cucumbers, tomatoes, peppers, basil, …everything was getting hit. So now I am trying out new nematodes and will try beneficial mites next. I need to learn to identify a lot more bugs, since there are so many beneficials out there.
Thank you for your post. I found your blog while looking for diseases on citrus. I have several citrus trees in the South of France and my 4-season lemon is looking a bit weary. I thought perhaps chlorosis but it has not responded to treatment so I’ll try something else.
You had mentioned that the EU has banned most non-organic (chemical) pesticides, and this is true so we have had to become creative in order to preserve bees and other beneficial insects.
I do use Neem oil with Savon Noir (a mild soap) early in the spring before the beneficials arrive. If one is careful to use it at dusk (in the evening) after bees have gone home and not spray if you see them. This help control outbreaks of several pests before beneficials arrive. In late spring I stop spraying Neem and use water to keep the remaining aphids in check and thwart spider mites (the climate here is dry in the summer like CA). The water on the citrus leaves encourages lady bugs to make your trees their home and I always have several hundred hatching throughout the summer.
Sorry if you addressed this elsewhere
I’ve got a citrus that’s about 5 years old and has fruited for 2 years. Its leafing out now but no flower buds. Should I water stress it to force flowering?
Hello Greg,
I came upon your post while searching to identify a growth out of my lime tree and Wala, you explained it perfectly, it was a growth sucker. I went right out and clipped the branches out. Then I read on about leaf miners, my lime tree had plenty. I confess, I removed the affected leafs, applied some neem oil then added a sticky sheet to catch the intruders. All seemed to help, but now after reading about neem oil and pinching off leafs, I’ll be
More mindful.
I have a question about planting my lime tree. It’s probably 4 years young, was a memorial gift and has been growing in a pot but in the Bay Area and I moved to Southern California to palm desert. Completely different growing temps. I moved here in December 2021, dug a hole and planted it in a windy area of the yard, too windy so I planted it in another less windy area but was shaded, so I replanted back into a pot. Poor thing, I’m amazed it has fruit. I would love advice on where it should it be planted, I feel it needs to be but no idea what area of the garden. We do get some fierce winds at times and then there’s the beating sun. Currently it’s shaded by a beach umbrella as I noticed it was roasting. Surely it felt cultural shock coming from a bay breeze to harsh sun. Thank you
Hi Greg,
I am not likely to spray my garden with any chemicals because I just don’t want any of that in my small backyard garden. However, my dwarf meyer lemon tree has and continues to suffer from the most horrible curled, black-coated, squiggly-lined leaves I’ve ever seen.
The fruit are plenty and beautiful, but I seriously want to strip the 5yr old, 2.5ft tree of the 95% affected leaves. I’ve read that butterflies, moths and leaf miners are the cause. I’ve also seen spiders, earwigs, grasshoppers and other creeping, hopping and flying bugs in the tree.
I want beautiful leaves and fruit.
What can I do?
Thanks.
Hi Greg,
I’m curious what methods you’ve found most effective for dealing with ants and aphids. Thanks!
I totally agree with your method. I have done something similar for years. I encourage my citrus trees to flush new growth in the spring by using lots of fertilizer in late winter and early spring. The leaf miner never has a chance to attack the leaves. If the trees do flush in summer any damaged growth is removed. Never spray my citrus trees for leaf miner.