Feeding Rhododendrons

[Lawrence]

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]

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

[Maggi Young]

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.

[johnw]

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.....

[johnw]

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.