Stand Alone Pages

Wednesday, May 27, 2015

Why Is My Queen Palm Yellow?

This is not the queen palm mentioned in the question.
But this is a very common yellowing that occurs
to queen palm in our desert environment and our desert soils.
Q. I have a queen palm that is recently beginning to yellow. It's done well every year until this Spring. I Miracle-Gro the soil around it every two weeks from spring through Summer. I've given it Palm Food a few times a year. One nursery told me I am watering too much. I severely cut back the bushes on both sides of the tree that were overgrown and covering the base and trunk of the palm for the past couple years. Could that possibly have anything to do with it?

A. First of all, Queen palms are very difficult to grow in this desert climate and in these very difficult soils. They really have trouble because of our hot dry winds and hours alkaline soils that contain no organic material.

Now that we have that out of the way…

Yellowing of palm in our soils is usually related to a lack of iron reaching the foliage. You might try applying some EDDHA iron to the soil. This type of iron works at highly alkaline pH which other irons do not.However it should be applied to the soil in the very early spring before new growth occurs.

Applying iron to the soil this late in the season only corrects foliage produced after you apply it to the soil.  Older foliage, foliage that grew before this soil application, will not green up with a soil application. Yellow foliage must be sprayed with an iron solution to get it to green up. Applications to the foliage have to be done several times to be effective.
This is an example of an iron chelate
used for correcting yellow foliage on plants
with liquid sprays.You must adjust
the pH of the spray or use distilled water
for sprays like this to work.

Here is the proper way to mix and apply iron to the foliage:

  1. Mix only enough that you will need for spraying. It will not keep after you mix the dry ingredients with water. You must use it up.
  2. Use distilled water if possible. If you use tap water you will have to adjust the pH or alkalinity of the water for an iron application to the foliage to work.If you use tap water, add 1 tablespoon of white vinegar to each gallon of water to lower the pH.If you really want to be sure about the pH, use the pool test kits to get your pH between 6.0 and 7.0.
  3. After you have adjusted the pH, add the iron fertilizer to the water. Do not add the fertilizer first and then add the vinegar. If you use distilled water you can skip the vinegar.
  4. Add a good wetting agent such as EZ Wet. Why? This is not a gimmick. It is very important when spraying liquids, whether its fertilizer or a fungicide, on the leaves of plants. Follow the label directions but you usually add about 1/2 to 1 tablespoon for each gallon of spray. Add this at the very end and mix it into the spray mixture.
  5. Apply this spray when temperatures are cool, such as the early morning or evening. Pump up your sprayer and spray it on the leaves with enough liquid to wet the surface of the leaves or when you see the spray liquid beginning to drip from the foliage. Spraying the foliage for longer than this is wasting your time, spray mixture and money.
  6. This is a good wetting agent for applying liquid sprays.
    It is made from an agave extract and cold pressed.
  7. Repeat this spray in four or five applications several days apart. The normal way for iron to get inside the plant is from the roots. You are trying to get iron inside the plant in the opposite direction. This is much more difficult. You need multiple applications and a wetting agent such as EZ Wet to get it inside the plant.
I would agree that if you water too often or if you have poor drainage you would see yellowing like this from root damage because the soil is kept to wet. All palms should be watered infrequently but with quite a bit of water when you do apply it.

Other mineral deficiencies that can cause yellowing on palm include manganese, potassium and magnesium. The better palm fertilizers will contain these elements and you will see it in their label. I noticed this is not the case with some palm fertilizers.

I don't see why cutting back shrubs next to the queen palm would have any impact on it.

Queen palms look really pretty in San Diego. They are very questionable growing in the Mojave Desert unless you’ve got the perfect spot for them. Stick to more desert adapted Palms next time and you will have fewer problems.

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