Using JOBE spikes on mature rhodies

12 years ago

Hi all. I have some leftover Jobe spikes I want to use on the rhodies. The spikes are for citrus and fruit trees, but I figured it was close enough to use for the rhodies. I am trying to nurse them back to health from the terrible fungus they now have. For logistical reasons, I broke the spikes in half and had to bury them within 24" from the trunks. (box says 36") . I don't think the rhodies will get over burned, as the spikes slope down from the tree.

Does anyone see any problems with this? I'm a complete ameteur, so bear with me.

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Comments (4)

morz8 - Washington Coast
12 years ago
The fertilizer won't do anything to correct a disease or other health issue, it will only correct low fertility so not helpful unless a nutrient deficiency caused the problem.

Rhododendrons have low nutritional requirements compared to many shrubs and trees - more issues are likely caused by too much fertilizer rather than not enough.

You need to go back to your first question, first post, and try to identify which disease or environmental issue is affecting your shrubs. Treat or correct the condition only after that...
lairdwd
Original Author
12 years ago
Thanks for the reply. I know what the environmental issue is - when my roof was emergency roof raked in the winter, the rhodie were left in an overly moist environment for too long, which weakened the plant. That won't happen again, unless we continue to get record snow falls.

Regarding the JOBE spikes - the ship has already sailed there. I had some spikes and wanted to get rid of them anyway, so as long as the fertilizer formula for citrus/fruit isn't that far from rhodies, I think I'll be ok.
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jean001a
12 years ago
Okay, so according to your other post, where you link to images, the plant isn't diseased. The problem is environmental stress.

see
http://forums.gardenweb.com/forums/load/azalea/msg0612120929734.html?3http://forums.gardenweb.com/forums/load/azalea/msg0612120929734.html?3

Here is a link that might be useful: not a disesae
botann
12 years ago
Jobe Spikes are a waste of time in my opinion, especially on rhododendrons. As Morz8 says, they don't need much fert, if any, and too much causes problems. You get weak, soft, new growth suseptible to bugs and early frost. Since Rhodies have a fibrous root system, grinding up the spikes and lightly sprinkling them on the mulch above the roots would have been a better way to do it, rather than a concentrated spike.......if you do decide to fertilize them. I know, you already did. Fert will not help any fungus problems and may cause it on new growth.
I have a lot of rhododendrons and have never fertilized them while in the ground and they are very healthy. Of course, I'm in a different climate and don't shovel snow from the roof on them either.
Mike

Using JOBE spikes on mature rhodies

Comments (4)

morz8 - Washington Coast

lairdwd
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Using JOBE spikes on mature rhodies

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morz8 - Washington Coast

lairdwdOriginal Author

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botann

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lairdwd
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