anitje
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I think I am killing my rhododendrons. HELP!!!

I have a 5-6 foot rhododendron (as well as other plants) that I think I may have killed due to my own stupidity

I planted it spring 2012. I fertilized it mid-July for the first time and then went to Europe for a month. While I was gone it was a very wet summer interspersed with intense heat spells. When I came back I found at least half of it dead or almost dead, with branches devoid of leaves and others with leaves severely wilted and curled. There appears to still be some healthy growth with healthy looking green leaves and even some buds.

I brought a branch to my local nursery and the guy told me that he thought it was a case of phytophthora, but I think I over-fertilized it because I am an idiot. I think I burnt the root system. Is this possible? What do you think?

I have 8 purple gem rhododendrons that are about 1-2' tall that looked fine when I left and now look completely dead.

I also have a couple of climbing hydrangeas that I bought last year that dropped all their leaves, and I wonder if that is normal for this time of year, or if I may have killed those as well.

Is there anything I can do to try to salvage my rhododendron? Should I cut all branches where there are dead or dying leaves to their base or just above any visible healthy foliage? (the lower portion of the plant and the part facing in one direction suffered the most). Or is it hopeless? Is there anything I can do?

Please help save my plant. If you do I promise I will NEVER do this again.

tomc
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Rhodies & azalea will look better with several light applications (say 1/4 recommended application rate of miracid). But like most trees what they need is water and bark mulch to conserve the water they do get.


I have used bark mulch exclusively in leu of fertilization on many trees.

Did you chip the sides of their plant-out holes?

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rainbowgardener
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Having trouble putting it all together. You bought it (and I presume planted it) in "spring of 2012". "I fertilized it mid-July for the first time and then went to Europe for a month. " Mid-July 2012? 2013? If 2013, what happened in the 15 ish months between spring 2012 and July 2013?

You only mentioned fertilizing it once in mid-July of whatever year, although that says "for the first time" which sort of implies there were other times. When else did you fertilize it? If you only fertilized it one time, what makes you think it could be over-fertilized?

The guy at the nursery suggested root rot. Why are you discounting that suggestion?

tom's question about the sides of the planting holes speaks to the root rot issue. Especially if your soil is clayish, if you dig a planting hole, the sides of the hole can get smoothed out and hardened. Then it is sort of like putting your plant in a bathtub; the planting hole just holds water and you get the root rot.

anitje
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Joined: Wed Apr 25, 2012 4:12 pm

I'm sorry I was not clear.

I fertilized once, in mid-July 2013. When I returned a month later (mid-Aug. 2013) is when I noticed the problem.

I removed the burlap when I planted, as directed by the nursery that sold me the plant.

I am not discounting root rot (phytophora). I am not discounting anything, since others know much more than I do about this. The reason I think it may be due to over-fertilization is that two other rhododendrons not far away are doing ok, whereas 8 of 9 small rhododendrons in another part of my yard died at the same time. I also think a couple of climbing hydrangeas died, and they were in my front yard, removed from the rhodies with the problems. I can't imagine that I over-watered, but we had a ton of rain when I was gone. I think the plants were sufficiently mulched.

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applestar
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Can we start from the beginning? I'm having trouble putting it all together, too. Also please indicate where you are located. :?

The plant in question is 5-6 FEET tall and was planted last year? How big was it when you planted it? Was it so happy that it grew so big over the course of the past year? (suspecting weak rapid growth) or was it huge to begin with? (suspecting limited or stunted root system for the size).

Were the 2 others in the same area planted at the same time? What about the 8-9 dead others in another area?

-- I'm trying to figure out if they were established plants that were happy there and what changed
-- I'm also trying to figure out if the way you planted and cared for this and the other dead ones in the past year had anything to do with it (location, depth of the planting hole, amendments if any, watering regimen)

In other words, if there were established Rhodos there and the dead ones are newly planted or if the dead ones were established plants and were the weather/rain/drought? patterns significantly different from the norm? Were they dependent on being artificial watering schedule that were lacking while you were gone? Did they suffer some kind of set back over the last winter?

If over fertilizing was the cause, what kind of fertilizer and how much did you apply?

Just as a point of reference, very wet summer shouldn't kill them unless they were planted in low spots and sat soggy. They like plenty of water but need good drainage. I have to plant mine on mounds because of the clay soil. But this means they are also very susceptible to drought conditions because they are shallow rooted. Also, they can't take too intense sun and should be kept away from south or west direct sun exposure. West if only very limited. I actually don't fertilize at all....



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