Magnesium or Iron Deficiencies ?

by Richard Chew

I have posted sometime ago on dealing with chlorotic rose.

Chlorosis is usually caused by iron deficiencies. Its symptoms are usually yellowing leaves with dark veins.

I have posted how I resolve this in http://rosegrowing.blogspot.com/2008/11/dealing-with-cholorotic-nozomi-rose.html

However it is often confused with magnesium deficiencies. Both have same symptoms but caused by different pH extreme. I very often mistook the symptom for the other.

Magnesium deficiency is usually caused by too low pH (soil too acidic).

Before treating the deficiencies, it is important to correct the soil pH first before attempting to correct the deficiencies.

Soil acidity could be caused by laying excessive brown mulch or excessive organic fertilizers like fish meal, bone meal, it is important to check what you fed the soil that may have lowered the soil pH.

My favourite method to treat acidic soil is by adding manure fertilizer, such as dry chicken manure or cattle manure. And then follow by liquid seaweed fertilizer. I would feed both soil and on leaves.



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Dealing with cholorotic Nozomi Rose - Part 4 (Conclusion)

by Richard Chew




This is an update since the last posting a month ago http://rosegrowing.blogspot.com/2008/12/dealing-with-cholorotic-nozomi-rose_22.html





The result is encouraging. New flower bulbs emerged. It successfully endured the rainy period in December.






Another bulb....




I have learned that most of the times symptoms of nutrient deficiencies may not necessary be corrected by supplementing the deficient nutrients. The likely possible cause is due to high soil pH that reduces the nutrient absorbtion rate, thus cause the plant to exhibit the symptoms. Correcting the soil pH will very likely improve the result.



The above picture was taken last November before the leaves withered off. I am led to believe that the continous rain during November and December had a dramatic impact on the soil pH, which in this case caused the chlorosis. Adding organic materials on top of the soil not just helped correcting the soil pH but also help reduce irritation to the soil organism like earth worms from the pelting rain at the surface.

In conclusion, I feel it is imperative that soil pH is checked before treating nutrient deficient symptoms. Another point I wish to highlight before I close, is that a month ago, I received a comment from a reader saying that this rose isn't a Nozomi rose. After checking from some other sources, I must admit that it is true that what I have is not a Nozomi rose.

Thank you for following my story in dealing with chlorosis. Hope this is good resource for you in dealing with plant diseases.

Wish you Happy Chinese New Year.



To go to original posting click here (Part 1)

Dealing with cholorotic Nozomi Rose - Part 3

by Richard Chew


This is continuation since my posting 2 weeks ago.



The result is very encouraging. Had quite a number of new growth.










The leaves are greener, though it was hit by continous rain, the leaves remained healthy. This is good sign.





In the next 2 weeks, I expect some bulbs to develop from these shoots.



What did I do since my last posting?

About a week ago, I added some brown mulch at the top soil and moist the soil with compost tea. It is not exactly the same compost tea that is commonly sold in nursery, this one was home-made. It is popularly known as AACT, which stands for Actively Aerated Compost Tea. I will share more about the ingredients and the process of making this tea in my future postings.













This torned leave, must have been caused by an insect or a bug. I believe it didn't taste good, therefore the leave remained (no big munch). I learned that bugs and insects usually target stressed out plant, because stressed plant produces higher amounts of amino acids thus provide better taste and flavour for insects to munch.



Putting it in another angle, healthy plants taste awful for insects. This is excellent natural insect repellant !!!



And another plus benefit is that hungry insects tends to target mites & mealy bugs especially if they can't find tasty leaves for food. In a way insects do provide some benefit though they are sometimes can be a real pest. They help control population of mites, aphids and mealy bugs.

Ooops... I am going off topic... Cut the long story short... bottom line is healthier plants keep pest away. This is indeed a very very good sign.

Ok... back to the topic.

Though it is still early to confirm my findings. I am quite encouraged by the positive signs. Considering the amount of rain that my Nozomi rose had to endure for the past few weeks, and the persisting chlorotic condition for months, I would say it is responding excellently well.

I am going to leave this plant alone and not 'tamper' with the soil for another 2 weeks. And shall examine how it progress with little 'human' intervention. The objective here is to find a 'lasting' remedy that corrects the root problem.

Just this morning I noticed some fungal mushroomed from the mulch. This is another good sign that the organism beneath the soil is actively at work!!

At this recovery rate, I believe I will see some new flower bulbs developing soon. And yes this Nozomi rose shall definitely feature in my January bloom posting!!!

Dealing with cholorotic Nozomi Rose - Part 2

by Richard Chew

I posted on 26th Nov on how I dealt with my cholorotic rose.


As I am writing this post, I learned some important research work on microbes that resides within the rizosphere of the roots.


It seemed at this stage of growth, the soil has to be fungi dominant, rather than bacteria dominant. When the soil is fungi dominant, its metabolic activities decreases the soil pH. This should helps the roots to absorb iron.


Upon learning this, I added brown mulch to increase the population of this beneficial fungi in the soil.




The mulch (brown) that is made of dry matter has to be added on top of the soil and not mix into the top soil. If it is mixed into the soil, it allows more bacteria to compete with the fungi to decompose the mulch. Fungi tends to thrive better in drier and brownier matter. Whereas bacteria works better on greener, fresher matter and more moist condition. This is not to say bacteria is not good, we need a balance of both, but for this treatment is meant to support fungi dominant.


And I also learned that I should avoid putting fertilizer that has N-P-K values higher than 10, as it may disturb the microbes in the soil. This isn't an issue to me, as I was already using organic fertilizer that is less than 5 N-P-K value.

Another thing that I did to increase the good microbes in the soil, was to collect the residue from my most healthiest rose of similar maturity (from water collector tray), and pour it into this problematic rose. Hopefully this transfer the good microbes and brings along the benefits.






As of now this is the current condition. I need to wait for another 4 weeks to confirm the impact. At least I have the assurance that I am on the right track. Just recently my Nozomi rose gave me this bloom. Despite its miserable condition, it still able to produce a flower. You can see the contrast of the nicely developed flower against the rusty spotted leaves at the background. There is still hope!




Nozomi rose is quite a hardy plant. It is a good ground cover. It grows horizontally. Hopefully in 4 weeks I get to see a more fuller and healthier ground cover.

Continue ...

Dealing with cholorotic Nozomi Rose

by Richard Chew



At this time of writing this posting, I am still finding ways to overcome chlorosis at my Nozomi Rose. Though infected with chlorosis, the stems looks healthy so there is still some good chance to recover this rose.


I replaced the top soil with more acidic organic matter. I used peat moss with mixture of grass clippings to aid aerobic decomposition.


Another ingredient that I add into the mixture were chili in slices . I chose chili because I have abundance of it grown at my garden. Chili like any fresh vegetable has 25:1 carbon nitrogen ratio. I particularly plugged the rotted ones, as they have lower carbon nitrogen ratio which makes it easier to decompose.


I've checked other resources for advise to treat chlorosis. In general the most acceptable advise are to spread sulfur or squeeze lime on to the soil to increase the acidicty. Basically acidicty of soil helps the roots to absorb iron. However most also commented that the results will not be immediate, it will take time for the bacteria to react after the application of sulfur or lime.



I felt that instead of adding sulfur that may interupt the microbial soil organism; and squeezing lime may have temporal effect, as it may leached by the expected monsoon rain in the coming months. I felt using urea will be a better alternative, as it not only improves soil acidicty, it has another plus factor that it increases the supply of nitrogen in soil.


Plants needs nitrogen to build cholorophyll cell at the leaves. Although chlorotic plants are usually associated with iron defiency, there is sufficient research to confirm its relation with nitrogen defiencies. Basically chlorotic plants needs very little amount of iron to build cholorophyll cells in new leaves. There is suggestions that very likely the required iron is so little that the soil may have sufficient iron to fulfill the plants needs.

The main problem is likely due to the inability of plant roots to absorb the ferum ions in soil. By increasing the supply of nitrogen, this will aid rizhosphere (bacteria that lives at plant roots) to accumulate iron for root uptake. I also learned that increased of phosporus will affect the uptake of iron in the roots.

Just to experiment the effectiveness of this treatement, I applied a teaspoon of urea at the outer perimeter on the top soil to avoid burning the roots and main stem. When it fully dissolved into the soil, I gradually mixed it with the rest at top soil, . Hopefully in a month time, more darker green shoots will appear.


Click to continue Part 2

Iron Chlorosis Signals Problems [EXT]

I included this site in this post to help us understand Iron deficiencies.

http://www.ext.vt.edu/departments/envirohort/factsheets2/fertilizer/nov86pr1.html


Iron Chlorosis Signals Problems


Contact: Diane Relf, Extension Specialist, Environmental Horticulture Posted April 1997 Chlorosis means "becoming green." The term was first applied to a human condition in which the skin took on a greenish hue. Today it is more frequently used to describe plants whose normal color is green, but which have a condition which results in a lack of green color in some leaves. Chlorosis in plants results from nutrient deficiency, insufficient light, or certain virus diseases. The most frequent cause of chlorosis linked to nutrient deficiency is iron chlorosis. This develops when a plant is unable to absorb enough iron from the soil. Sometimes the soil does not contain enough iron; but most often iron is in the soil but in a chemical form which makes it unavailable to the plant. Soils with high pH (alkaline) often bind iron in a form plants cannot use. Most plants do not develop iron chlorosis in neutral (pH 7) or slightly acid soil, but begin to develop yellowing as soils become more and more alkaline (pH>7). Such plants include rose, iris, firethorn, spirea, apple and peach.


Some plants require very acid soil and develop iron chlorosis when they are grown in soils which are not acid enough. Such plants include azaleas, rhododendron, holly, hydrangea, blueberry and pin oak.


Iron chlorosis is different from other types of chlorosis; it affects young, new leaves first. Other forms of chlorosis often affect older foliage initially. Leaf color of plants with chlorosis ranges from yellow-green to almost white. Leaves showing iron chlorosis often retain green veins. In severe cases, leaf margins may be brown and die, and eventually entire plants may be killed. Even in mild cases where yellowing is slight, growth is reduced.


Iron chlorosis is usually associated with deficiency or unavailability of iron in the soil but it may also appear when roots are damaged by overwatering, poor drainage, or overfertilization. Any condition that kills roots or does not allow feeder root development can lead to iron chlorosis.Treat iron chlorosis by eliminating the cause. A soil test will determine soil pH. Alkaline soil, or soil which is not acid enough, may be treated with sulfur or iron sulfate to make it more acidic. Poorly drained soils should be improved and plants subject to iron chlorosis should be watered carefully. The color of plants several months after soil is amendmended will indicate need for future treatment.


To achieve temporary improvement in leaf color, there are materials available for providing iron quickly to plants. Iron chelates are organic compounds containing readily-absorbed iron. They can be placed in the soil for absorption by the roots or sprayed in dilute form directly on the leaves. Since the chemical concentration of the compound may vary with manufacturer, carefully follow directions given on the package.


When fertilizer is sprayed onto leaves the process is called foliar fertilization. It is a good way to supply some nutrients, including iron, to plants rapidly, but foliar feeding is not a substitute for good soil conditions. Foliar fertilizer can supplement soil nutrition at a critical time, but to eliminate iron chlorosis, correct the conditions causing it.


(Prepared by Virginia Nathan, Extension Technician, and Diane Relf, Extension Specialist, Environmental Horticulture, Virginia Tech, Blacksburg, VA 24061-0327.)