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santi_rodriguez

Rosemary chlorisis, can't find a solution

santi_rodriguez
17 years ago

i have three plants of rosmary the bush type, im from uruguay and i bought this plants last spring and they were fine, soon after i put them in my garden all three of them developed chloriosis having whitish leaves and loosing much of their aroma.

I've tried everything adding iron chelate,compost mulch, manganese, gardening sulphur, even some vinegar, but nothing seems to work.

I would really apreciate any help that i could get, cause they are great plants and i don't seem to find a solution.

Comments (7)

  • ksrogers
    17 years ago

    It may be due to too much water. The problem arises from overwatering or poor drainage. Suggest that you add some sand or other means to keep moisture down a bit more. Be careful using the chemicals as they are quite suseptable to suddent changes in soil chemistry. When the plants are doing well, the leaves get somewhat sticky like pine would do. Digging them out carefully, and adding some sand or other kinds of inert matter under the root system, as well as mounding up the soil afterwards would help to give a bit more drainage. Basically plant them in a slight hill.

  • santi_rodriguez
    Original Author
    17 years ago

    I don't think its overwatering, cause the soil they're in is a very well drained one, dunno what it is but it sure drains well. Maybe it isnt chloriosis, cause i did a bit of research and i found out that the new leaves are the ones that develop chloriosis and in my case they are the older ones,and they do not turn a yellow that suggests wilting, but more like a leaf decoloration.

    Please any help on what is happening or how to treat it is very welcome, by the way thanks ksrogers i'll try mounding earth round their trunks and see how that works.

  • ksrogers
    17 years ago

    Older leaves on the lower parts of the plants will die out eventually. This is quite common. If you want more bushy growth, maybe trimming off some of the longer stems will help. Because rosemary is similar to pine, it does like a bit more acid compared to other herbs. Acid based fertilizers are OK, but use sparingly. You mentioned iron, sulphur and vinegar, these are very acidic and if this is a small plant, may be just too much for them all at once. Garden sulphur doesn't break down quickly and it can take about 3 or more months to do its work. Any soil ammendments will take several months to show up in the plants growth. If your using all of these treatments at the same time, they could all be slowly killing the plants.

  • santi_rodriguez
    Original Author
    17 years ago

    Thanks ksrogers for your help, but the leaves aren't wilting cause its not only the lower leaves its the whole plant, it starts as white spots and finally ends with a whitish leaf. I checked for pests but there were none visible, i hope i could upload a picture or something but i cant cause i dont own a camera. Thank you for your help

    I initially assumed it was chloriosis cause some roses in the same bed suffered from it but those are better now but the rosemary is not.

  • ksrogers
    17 years ago

    White spots may be a fungal infection, like downy mildue or some other leaf fungus. Repotting or removing the original soil may help some. When you do, use a soil that is sterilzed. A mild spray of neem oil can help too. The other option is a mild copper sulfate spray. They sell a product that has a 'fatty acid soap' mixed with copper, and coats the leaves of plants. Spray as much of the underside of the foliage too.

    PS: digital cameras are very cheap now and quite affordable. I send up photos to the Photo Bucket site, where I can link to them here. If you do invest in one, look for a good 'macro' setting, used for closeups. Mine goes down to an inch from an object, its a Nikon.

  • santi_rodriguez
    Original Author
    17 years ago

    ksrogers I applied the copper sulphate today,will this bring the green color back to the leaves? or will it prevent it from infecting the younger leaves? What results should i expect?

  • ksrogers
    17 years ago

    A light very coating will only help to prevent more leaves from being consumed by the fungus. The ones that have turned white might recolro, but I doubt it. Try moisening your fingers and rubbing some of the white color leaves and see if they show up any green under the coating. If so, then I would use a light spray of the copper sulfate again in about 3-4 weeks. Not sure what kind your using, but must assume its a mixture that is liquid and is mixed with water. There is one really good one for tender plants, as it contains fatty acids that help to give the copper more leaf coverage, and that seems to adhere better, as well as using less copper. If the leaves start to die or turn brown, I would spray the plant with a fine mist of water to rinse off some of the excess copper. It is powerful stuff and is also used in protecting fungus on grape vines and grapes. One other help is the use of plenty of sunlight, as it can also help to kill some of the fungus growth. Usually when foliage gets damaged, it will not return, but new growth should occur soon.