Hello, I received a dwarf meyer lemon tree last October. I would guess that it is about 1-2 years old. We planted it in a very large container. We live in Southern California near the coast, so its always around 70-80 degrees F here. The tree gets about 6-8 hours of sun a day on our south facing patio. We have about three lemons growing on it currently, all of which are very green, and in varying stages of growth. None of the lemons are bigger than a small lime so far. We also have several other plants on the patio in separate containers, including blueberries, strawberries, a pineapple bush and rosemary. I trimmed the very top of the lemon tree about two months ago to promote fuller growth. The tree has a bunch of new growth on one side. However, some of the new leaves, and most of the old ones, are dying and falling off the tree. The newer growth seems to have been attacked first. The green part of the leaves has been eaten or has eroded in spots all over the leaves. There are no holes in the leaves, but what remain are dry brown splotches where the green used to be. Whatever this is seems to be spreading to all of the leaves. I can't figure out if this is a pest, or a disease or what. It is definitely not scale - these spots are not raised (in fact, its more like an indentation in the leaf) Yesterday, I saw a small white spider crawling around on the tree, which I promptly killed with insecticide. I have not seen any other spiders. I don't believe that it was an aphid because it had 8 legs and was bigger than an aphid. Also, there was only one. Any help would be greatly appreciated. I love this tree and its very sad to be unable to help it. Thank you so much for any advice you might have. I'll try to post a picture soon.
I don't believe the trees problem has anything to do with bugs, or insects. I believe it is probably from being a small tree over planted into too large of a container. How tall is the tree, and how wide and deep is the container that you planted the tree into? What fertilizer do you use, and how often do you feed the tree? Without a picture it is impossible to be sure of the problem. - Millet
The tree is about 1.5 ft tall (measuring from the surface of the soil) and just as wide. The container is 24 inches in diameter, and about the same depth, perhaps 28 inches. The container (plastic, with holes in the bottom) and the tree were purchased from an Armstrong nursery at the same time and under their recommendations. We use the fertilizer they recommended - E.B. Stone Citrus and Avocado food, which I believe is water soluble. Per the instructions on the box, we fertilize approximately once a month, and we water so that the water drains out of the bottom of the plant about every two weeks or so. I am fairly certain that we overwatered the plant in the beginning, because the oldest leaves have yellow tips. The roots of the plant extend to about 3" from the edge of the container. I'm particularly vigilant about checking deep in the soil to see whether the soil is damp before watering and I always run into roots extending away from the rootball when I do that. I know this is very difficult to diagnose without a picture - I will post some tomorrow, I'm not at home right now. The spots on the leaves have no yellowing or dark browning - its as if the chlorophyll has been stripped in spots. Also, the ends of some of the stems which have been stripped of their leaves are turning brown and dying. Should I trim those? Again, thanks so much.
Here are my lemon tree pictures. Any help would be wonderful. Please note that the tree was leafier and taller before this necrosis began, and before I trimmed the top and sides a couple of months ago. You can see in the close ups the most damaged of the leaves are in the middle (which are part of the newer growth). Whatever this is has spread to the older growth which is beginning to display similar spotting, although not nearly as severe. The newer and undamaged growth is on the right, and the older growth is on the left. As you can see in certain pictures, some of the stems without any leaves on them are beginning to brown at the tips. I have not watered the tree in more than 2 weeks. I checked the soil last night and beneath the top layer, the rootball is still damp. Is it possible that this damage is from pesticide use? The pesticide is for house plants and vegetables/fruit. I don't know the chemical contents.
It is always possible that the damage could be from the spray, but I would rather doubt it, as the spray was for house plants and vegetables. The spray is probably a pyrethrum. My guess is that the damage is from a combination of things. The growth medium looks to be mostly peat moss with a little perlite. As you received the tree in October it has been in the container for nine months now, so I am sure the peat moss has settled quite a bit during this time. The main problem with potting mixes containing mostly peat moss, is the degrading of the moss followed by compaction. Therefore, the medium begins to hold to much water and for to long, and consequently does not hold enough oxygen. I think the main problems are the size of the container in relation to the size of the tree, and the make up of the potting soil, causing a build up of a high level of soluble salts, high level of water, high level of carbon dioxide, and a low level of oxygen. The biggest mistake is usually made not in the type of pot but by using too large a pot. People think that they are doing the tree a favor by giving it a lot or room. But if the tree doesn't grow fast enough to use all of the space, trouble occurs. An oversized pot can become waterlogged easily, and then the plant suffers from lack of air. A good potting mixture for citrus should be 60 percent coarse material such as pine bark or coconut husk chips (CHC). An example of a common citrus growth medium is 3-parts coarse pine bark, 1 part peat moss, and 1 part coarse sand (not play sand), or 4 parts CHC and 1 part peat moss. Soluble salts come from the fertilizer applied and the irrigation water used. They are removed from the potting soil by being taken up by the roots, and being flushed out of the container. However, in containers that are to large, the root system does not fill the container, and the salts build up. Symptoms of soluble salt damage are: 1. Leaf tips and margins brown and necrotic. 2. Leaf drop, 3. Slow growth, 4. Root damage, 5. If not corrected soil surface can get a buildup of white powdery residue. - Millet
Millet - thanks for all of your help. I really appreciate it. I have definitely seen a white powdery residue on the soil surface (but not for several weeks), so I am sure that you are right, and the soluble salts aren't getting flushed out. Plus, as you can tell in some of the pictures, there's salt residue on the bottom of the container. Moreover, the last time I watered, the water didn't drain very well out the bottom. I also think that the white marks on the stems could be salt damage as well. When we planted the tree, we used 1/2 cactus mix and 1/2 potting soil, which I imagine was mostly peat moss with a little perlite. The cactus mix looked like the coarse sand you are referring to. We use hard water to irrigate the tree and I'm sure that's part of the problem too. I'm going to start watering with distilled water, lay off the fertilizer for a little while (since the growth is actually quite fast anyway), and replace the soil with your suggested mixture in a smaller pot (or use less of the container). When the tree finally dries out, I'm going to water so that at least 10% of the water drains out the bottom. I'll report back (hopefully with better news). Thanks!
I find meyers to be a difficult container plant. In the ground I have much better luck with them. I have bought several meyers that garden centres were unloading because they looked similar to yours. I got them pretty cheap. Incidentally they were grown by Monrovia Growers in California. (They normally produce a pretty good product and I believe it is more to due to how the plant was treated once at the nursery) I have found that the nursery pots may have been too small for the root structure. I managed to bring them back with a little tlc. I would carefully check for some sort of bug either in the soil or on the plant. Have you checked for scale and spider mites? Light Horticultural oil mixed with a teaspoon of Dawn dish soap seems to rid Citrus plants of unwanted pests. Do you know who produced the tree? If there are no visible pests, I would guess that you tree may not getting enough water at its roots or the roots have suffered some sort of damage. Millet do you think using distilled water is overkill? We have very soft water here in Vancouver so hard water problems is not something I have to contend with. Greg
Update on my meyer lemon tree: Well, there's good news and very bad news. I took your advice and after waiting until the plant was dry, I watered with mostly distilled water (we have very hard water here in San Diego) so that a lot of water drained out the bottom of the plant. Unfortunately, I haven't had a chance to repot the plant in something smaller and with the CHC - its a big job and requires two people because the pot is so heavy. Since the watering, the salt damage seems to have ended - there are no more weird spots on the leaves, and the new growth isn't showing any spots either. But all of the old leaves have completely fallen off. The new leaves (on the right side in the pictures) are all still there, but they have light edges and dark veins, and are curling a bit. I can see that the tree is trying to create new leaf growth, but its very slow. There are no bugs or scale (at least, that I can see). I believe that this means that I need to add nitrogen to the soil (for leaf growth and for the green color) but I'm worried that I'll have salt damage again. We also took the remaining lemons off in order to have the plant focus on leaf growth. After actually transplanting the tree into a better pot with better soil, should I start using Osmocote instead of a monthly fertilizer? I am currently using E.B. Stone organic citrus and fruit tree food, which is a 7-3-3 and contains Blood Meal, Dried Chicken Manure, Bat Guano, Alfalfa Meal, Kelp Meal, Potassium Sulfate, Humic Acid, and soil microbes including mychorrhizal fungi. Again, any help would be wonderful. My tree is very sad looking right now.
Hollie, fertilizers made up of animal manures, vary greatly in nutrient content. The age and the type of manure create many variables. This makes it almost impossible to know how strong it is. As a rule, the older the manure, the less nutrient value. Because manures have a VERY high content of soluble salts, they are not suitable for containers. Generally they are used only in soil beds. An Osmocote formulation such as 19-6-12 would be a good fertilizer to use. Osmocote also has formulations that contain both the macro ingredients NPK plus all the trace minerals. I use Osmocote on my trees with good success. As citrus are heavy feeders I add a little more than the label rates. I also fertilize every now and then using a standard chemical fertilizer. Lastly, slow release fertilizers rarely cause any problems with high soluble salts. - Millet
