My last post was very helpful in making my meyers lemon tree heathy again.. But now a few of my new growth, on the tips of the leaves they are turning a dark green and are very very limp.. They dont seem like they are drying out or anything they are very soft and limp.. But not too many of them.. Now I also have a key lime tree and it looks as if there is something crawling inside some leaves.. I have used SaferSoap on both of the trees for about 3 weeks now to get rid of some bugs that I have seen crawling around the plants.. I havent really seen much of them anymore.. But Im not to sure if the things in leaves are still causing problems.. Any idea on what they could be and how to get rid of them or keep doing what Im doing to get rid of them.. Both of the trees are potted and are outside and get about 8-10 hrs of sun.. I live in Tx and right now its been about 95+ degrees out with high humidity and weve been getting a decent amount of rain.. I water when they feel dry which is about every other day or every other 2 days.. I fertilize with Nutri Star citrus fertilzer about 2-3 times a month.. Ill try to post some picture to be able to give you a better idea of what im seeing.. but I just got home from work and right now its about 1:30 am here so obviously I cant.. But otherwize.. any suggestions on either of the tree would be helpful..
It is always difficult to suggest how often to water container citrus because it is so dependent on conditions and the media, but every other day seems like too often unless you have very fast draining media with lots of air spaces. I live in a similar climate, but generally do not need to water more often than once a week--maybe 5 days in really hot-dry weather. I use a very chunky mix with pine bark that drains fast, so even when it rains every day as it often does here in the summer, the trees do not suffer from symptoms of overwatering. The problem you are seeing from insects inside the leaves is probably citrus leaf miners--CLM. There are 2 ways to try and reduce their effects; spray new flushes with 1% horticultural oil every few days--but only if you can spray early in the morning when temps are below 85F, (oil only deters the adult moth from laying eggs), other spray that can kill the larvae inside the leaf, is spinosad. If you have very young trees that will not bear fruit in the next year, you can use a systemic--imidacloprid--that is what many commercial nurseries use.
Well I only water when I see that the leaves are curling up on themselves and that the soil is dry.. If the leaves are curling and the soil still seems a little damp Ill just spray the leaves with a mist to get a little moisture going.. And since I get home most of the time around midnight, thats when Ill usually water them.. Is that okay or should I try to water during the day so the soil can kinna dry out better..
Misting the leaves is not going to do much to help a tree that has insufficient, to no water, available for the roots to take up. Your method of watering is putting stress on the tree that the tree does not need. Stick you finger in the top couple inches of soil, and when it feels rather dray (not bone dry) than water the container. When watering your tree, water it thoroughly, so that 10 percent of the water you apply drains out the bottom. Fertilize at least once a month. - Millet
The pictures do suggest CLM (miners)--in the single leaf picture, the miner trails are on the bottom of the leaf and that folded crease in the leaf is where the pupa is, if it has not hatched. If you look carefully at active trails, you can see the larvae near the end of the trail--they look like a tiny yellow worm. When they are mature, they will fold the leaf to form a cocoon--usually near the edge. Your tree is not heavily infested--in severe cases, there will be few leaves that are not affected and many will have almost the entire surface of the leaf mined--top and bottom.
Well thanks skeeterbug for the info.. My tree is putting out limes so Ill just keep trying the horticultural oil.. Any info about the darkening leaves on my lemon tree.. Or is that a result of my watering?? Really hadnt gotten any info back on that..
This was a good thread for me to learn about the leaf miners CLM. However, can someone suggest a product that I should purchase to deal with these creatures? Right now my Eureka Lemon is struggling with other pests so any treatment will not interrupt the fruit cycle. I want to get this tree healthy now and keep it that way. Product names? Thanks, Mouse
If you have fruit or expect fruit in the next yr, you should not use a systemic. The two other products that you can use are horticultural oil and spinosad. The oil should not be used at temperatures above 85F. I spray early in the morning and I only spray new growth--I spray as often as necessary to keep the new leaves coated --usually about 3 days. Oil does not kill the miners, but it discourages the adult moth from laying eggs on oily surface. Spinosad is available in a variety of brand name products--look at the active ingredients--the one I use is Fertilome "Bagworm miner and borer" or something like that.
Following up on the watering issue. A primary reason that people let their soils dry out before watering again is to aerate the soil. As soil dries and wets again the air is forced out through the soil by the infiltrating water and as it dries is air is drawn back down through the soil again. It is unnecessary to get totally bone dry soil in order to effect this "soil respiration" Just let the soil dry reasonably rather than wait for leaves to curl. Once air has turned over in the soil - which doesn't require a complete dry of all the soil - then moist soil is the goal. Water is the catalyst for virtually every other process working in the soil/root contact point other than air. -- The Dwarf Fruit Trees Blog
joshuaslocum, what you write concerning soil air porosity is certainly correct. The best growth medium for containerized citrus trees is a light, permeable, fast draining soil with at least a 20-25 percent air porosity. Such a growth medium does not require a drying process to regenerate high "soil" aeration. Air is drawn back into the root zone just as the water drains from the container's bottom. Use of bulk ingredients such as CHC, pine bark, or cedar chips in the proper proportion provides such a medium. - Millet
Joshuaslocum, you are right-- but I don't think Millet or I have ever suggested letting the media dry completely--that would be detrimental--moist media with air is the goal. Because of our humid environment and the shade cloth cover I use, my pine bark based media will stay moist for 5-7 days--CHC media here will stay moist even longer--but both have enough positive air space that would allow daily watering--something that Mother Nature happens to provide here for weeks at times. As I said, it is difficult to recommend watering frequency for others because it is so dependent on environmental conditions and the media--but if you have the right kind of media it really doesn't matter as much.
I am currently growing a Yen Ben Lemon in an extremely porous 50/50 mix of 1/2 and 1/4 inch CHC with no other filler. This gives a 60 percent container air porosity. Such a high porosity medium has advantages and disadvantages. The advantage is extremely rapid root growth (thus rapid scion growth). The main disadvantage, the medium requires extra careful regulation of nutrition, and daily watering. But such rapid grown!!! - Millet
I'm sure this is impossible to answer in any certain terms, but how much difference in scion growth would you say there is compared to the standard 4:1 CHC/peat mix? I have a couple dwarf trees about 2ft tall that I would love to grow as quickly as possible to at least twice that height. Do you think the difference would be significant?
Matt, there definitely is a difference in growth, but it depends on what you think is significant. A lot of the growth a tree can achieve depends on what variety of root stock the scion was grafted onto. Dwarf root stocks are naturally slow. The Yen Ben Lemon was a 12 inch tall tree at Paulino Gardens and was still "growing" in a small 4 inch pot when I purchased it on August 1. It should have been transplanted, but never was. I washed away the growth medium that was left and spread out the roots as I filled a 3-gallon root maker container with the 50/50 CHC. I have to water it every day due to the high daytime temperatures. It is now about 18" tall and 25" wide. I water it with 150-PPM NPK solution each time. - Millet
On the original subject of my infestation, I have sprayed the tree with the oil product. How long until the black residue is gone? Should I attempt to hose it off? Thanks!
Unless you wash the black residue off it may stay on for a considerable time depending on conditions (sometimes it will dry up and flake off). The oil should have killed the source of the secretions that the sooty mold was growing on, so now you can wash it off.
You can wash off the sooty mold as soon as four hours after the oil application, or the day following the oil application. The oil spray will make the sooty mold come of a lot easier. - Millet