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Author Topic: Feeding Rhododendrons  (Read 2298 times)

Lawrence

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Feeding Rhododendrons
« on: January 10, 2016, 11:35:55 AM »
Bought some fabulous dwarf Rhododendron's from Glendoick last year, growing in pots, should I be feeding with a weak ericaceous liquid feed now to improve flowering?

Graeme

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Re: Feeding Rhododendrons
« Reply #1 on: January 10, 2016, 05:41:46 PM »
Lawrence

I keep Satsuki Azaleas - but to be honest I never feed them before they flower - but as soon as they have I take off all the seed pods - and then once they have created their extension growth clip out the growing points.

Feed - seaweed extract spray once a week after flowering till late September - enmag from as soon as the flowers have gone over and they have had all the seed heads removed
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Maggi Young

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Re: Feeding Rhododendrons
« Reply #2 on: January 10, 2016, 06:24:25 PM »
Graeme's method seems sound, Lawrence. 

I think keeping potted rhodos/azaleas  properly hydrated is probably the most important  factor to  keeping them healthy.  If they suffer drought through summer and autumn then bud set will be  adversely affected.  A feed of Miracid from time to time  does them good. (Miracid is one of the Miracle-Grow family of plant foods)

 Drought can lead to  loss of formation of flowering  growth of  rhodos planted in the ground too, of course.

Margaret Young in Aberdeen, North East Scotland Zone 7 -ish!

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johnw

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Re: Feeding Rhododendrons
« Reply #3 on: January 10, 2016, 06:55:53 PM »
We run our potted rhodos in the cold greenhouse on the dry side during the winter.  Over-watering during this low light season can lead to root rot.  No feed whatsoever until May though always a good idea to have a bit of superphosphate in the original mix (0-20-0) to help with bud set.

The past 2 summers have had extremely dry periods in July and August and the we have never seen such flowering last Spring - after a horrendous winter - buds set this autumnn is phenomenal.  In this climate a good summer drought does the trick, it however should not persist much longer than mid September as buds can abort or the first rain can trigger flowering in some.

john    - torrential rains on the way.....
John in coastal Nova Scotia

johnw

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Re: Feeding Rhododendrons
« Reply #4 on: January 11, 2016, 08:37:38 PM »
Should have mentioned re: summer watering of potted rhodos, severe drought can be fatal as Maggi states.  One missed watering at a critical point of dryness and the plant may well recover or not, the second time that is less likely.  What I find is that the resultant root damage from the dryness can lead to a fatal bout of Phythophthora when weather conditions are conducive.

Here in NS we have 2-3 days of hot humid summer weather, one false watering when the soil is already moist can lead to root rot and death.  For this reason the touchiest potted rhodos  - Taliensia, Neriiflora, Thomsonia, Uniflora, Lepidota, reds, yellows are always placed under an overhead clear roof to prevent a rain-drenching when already moist. Mid-June to early Sept.  This past summer was the worst for steam bath weather and though the temp only hit 28c once the warm humidity was relentless, only lost a handful of the usual suspects.

Opened the mail today to find a motherlode of seed - R. lowndesii, R. ludlowii, dwarf yellow Menzesia 'Moonlight', Enkianthus cernuus v. rubens and dwarf R. schlippenbachii (under 30" in 25 years).   Doesn't get much better than that, happy to get the likes in a decade's worth of gifts!

johnw - +11c. Torrential rains overnight, sunny & foggy today & glorious.  Temps to plunge, snow gone.....typical.     
« Last Edit: January 16, 2016, 01:25:50 AM by johnw »
John in coastal Nova Scotia

 


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