Wednesday, November 26, 2008

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