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  Pip Howard June 6, 2010 at 5:28pm

  Hi Roger, I have seen the Oleander leaf scorch first hand and it didn't look quite like this, but I really hate to say it but this doesn't look good at all. Have you a photo of the branches and stem? Also have you fed this year and if so with what?. Prune off one of the healthier stems close to the damage and expose the xylem and check for mottling and dark staining. Did the leaf came away very easily from the stem when picked?
  
  Sorry for all the questions but might be able to help as have a great book on mediterranean plant diseases.
  Cheers Pip
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  Bigyin June 6, 2010 at 6:01pm

  Hi Pip,
  I haven't any photo's. I took three of the oleander the other day to post on here and when I tried to upload them to the PC, the camera's gone on the blink, hence the scan.
  The yellow leaves are scattered randomly on the lower part of the plants at the moment. One or two have fallen off and yes, they do come away easily. I've had a few yellow leaves in previous years but not as many as at present. They've recovered on their own previously.
  I gave them some Nitrofoska Suprem end of March, early April (column 2 in this table)
  http://www.compo.es/compo/WebApp?Resource=IdealPortal.Page&Node... and I only water them about once a month during dry spells.
  I've just been out and pruned a stem a few inches below a pair of yellow leaves (which are the first two on the stem. The bark surface looks lighter and dryer below the yellow pair but everything above looks fine. There's no staining on the cambium itself and the cross section doesn't look like the verticillium wilt that hit my olives last year.
  I feel legless without the camera. Thanks for coming back by the way.
  
  Pip Howard said:

  Hi Roger, I have seen the Oleander leaf scorch first hand and it didn't look quite like this, but I really hate to say it but this doesn't look good at all. Have you a photo of the branches and stem? Also have you fed this year and if so with what?. Prune off one of the healthier stems close to the damage and expose the xylem and check for mottling and dark staining. Did the leaf came away very easily from the stem when picked?
  
  Sorry for all the questions but might be able to help as have a great book on mediterranean plant diseases.
  Cheers Pip
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  Pip Howard June 6, 2010 at 6:24pm

  Hi, from what you say it really doesn't sound like leaf scorch at all, but more possibly climactic or the result of the spraying, either yours or is drift spray from surrounding land possible? - wouldn't take much to hurt these plants. I have to be honest and say that I have a feeling that they didn't like the nitrofoska suprem - when was it applied? any chance of slight overdose? but my hunch is that they will recover from this.
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  Bigyin June 6, 2010 at 6:51pm

  I didn't spray the fertiliser. I scattered granules around the bases and watered it in. Must admit I didn't pay much attention to dosage. I think it's unlikey to be drift from elsewhere as the garden is at least 100 metres in all directions from the nearest fields which are citrus. The farmers top spray these with various pesticides but carry out mechanical weed control. There's been no damage to our other flowers in the area. I hope you're right about them recovering as there's a lot of them and I'm planning to plant a lot more. I'll keep you posted.
  Thanks once again for your help Monseiur.
  
  Pip Howard said:

  Hi, from what you say it really doesn't sound like leaf scorch at all, but more possibly climactic or the result of the spraying, either yours or is drift spray from surrounding land possible? - wouldn't take much to hurt these plants. I have to be honest and say that I have a feeling that they didn't like the nitrofoska suprem - when was it applied? any chance of slight overdose? but my hunch is that they will recover from this.
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  Claire Brown June 6, 2010 at 7:37pm

  It may not be anything too serious, - Oleander is an evergreen, and at this time of year they are shedding leaves, - my magnolia grandiflora in my front garden covers my border and drive each week at this time of year, it also has some leaf splotching. The recent very dry weather won't have helped, - so my advice would be to rake up and bin fallen leaves, in case there is any fungus or virus, and to water.
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  Pip Howard June 6, 2010 at 8:30pm

  I think what troubles me, (not about the plant itself but in trying to get to the bottom of this), is that the process of abscission for magnolias and similar semi evergreens usually only occurs on the older leaves - not so here. My guess is that it is what you say Claire is absolutely right, and that for some reason the strong fertiliser has resulted in the weaker new growth being affected rather than the older growth. I have seen this occur on containerised nursery stock and usually results in a stronger form therafter. The book i have is now available to view online - European Handbook of Plant Diseases - but as with 'human' books on illness it always tends to lead to panic in that all the symptoms can be viewed at any one time on a specimen in my garden - 'gardeners hypochondria'.
  Hope to hear about the Olives soon btw
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  Bigyin June 6, 2010 at 10:54pm

  Hi Claire,
  I didn't realise they shed leaves as a matter of course. The weather here is hot and dry anyway this time of year but it doesn't seem to bother them as a rule. They must be pretty hardy as they grow them up the middle of the motorways. I think I'll take your advice about watering (although we some some light rain today, first time for nearly a month) and go a bit easier on the fertiliser next time.
  
  Claire Brown said:

  It may not be anything too serious, - Oleander is an evergreen, and at this time of year they are shedding leaves, - my magnolia grandiflora in my front garden covers my border and drive each week at this time of year, it also has some leaf splotching. The recent very dry weather won't have helped, - so my advice would be to rake up and bin fallen leaves, in case there is any fungus or virus, and to water.
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  Bigyin June 6, 2010 at 10:57pm

  I'll try to get my camera repaired (or replaced) as soon as poss so I can post a better visual. I'll also try to get cracking on the olives.
  
  Pip Howard said:

  I think what troubles me, (not about the plant itself but in trying to get to the bottom of this), is that the process of abscission for magnolias and similar semi evergreens usually only occurs on the older leaves - not so here. My guess is that it is what you say Claire is absolutely right, and that for some reason the strong fertiliser has resulted in the weaker new growth being affected rather than the older growth. I have seen this occur on containerised nursery stock and usually results in a stronger form therafter. The book i have is now available to view online - European Handbook of Plant Diseases - but as with 'human' books on illness it always tends to lead to panic in that all the symptoms can be viewed at any one time on a specimen in my garden - 'gardeners hypochondria'.
  Hope to hear about the Olives soon btw
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  Bigyin July 3, 2010 at 10:40pm

  Glad to report that after a couple of rainy nights and a couple of good soakings with the hose, things have improved a bit. Next question re Oleander. I have about 45 established plants forming a hedge and a boundary between the "garden" and the rest of the wilderness. I need about another 250 to finish the job which will obviously be expensive. I've read on t'internet that they're easy to propagate by either putting cuttings in water or in soil. I've tried both methods a couple of times but they just die on me. I wondered if rooting hormone powder/solution would help. Does it actually make a difference ? I have loads of opportunities for propagating here but I don't seem to have the green thumb.
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  Bigyin July 3, 2010 at 11:11pm

  Thanks John. They're very common here in Spain. They grow quickly and do a good job as a windbreak. Mine are covered in flowers right through the summer. They use them a lot here as headlight barriers down the middle of motorways. Another benefit is that they are so toxic that the rabbits don't touch them.