rhododendron
 

I have a dwarf rhododendron which has flowered two years running, but just after flowering this year, the some of the leaves went bright yellow, some have little(what looks like bites in them) and the whole plant looks very sick..what can I do?

On Mon, 11 Jul 2005 20:01:34 +0000, solaara
wrote:


I have a dwarf rhododendron which has flowered two years running, but
just after flowering this year, the some of the leaves went bright
yellow, some have little(what looks like bites in them) and the whole
plant looks very sick..what can I do?


It may be sick, it may be OK. Old leaves on rhodies do sometimes go
bright yellow before dropping and there's no cause for alarm. OTOH it
may be chlorotic due to alkaline soil or watering with hard tap water.
The bites on the leaf edges are insect damage, probably caused by a
leaf-cutter bee. Or it could be dying.

Has it made any new growth since it flowered in the spring? If it has,
that's encouraging. If not, it may mean the roots are diseased and the
plant is dying.

Is it in partial shade? Do you mulch it to keep the roots cool and
moist? Do you water it in hot dry weather? Do you use rain water or
tap water? Is the tap water hard? They don't like alkaline soil or
hard tap water. Use rain water from a butt if your tap water is hard.

Do you feed it occasionally? Most plants like it little feed now and
then. You could feed it with an ericaceous feed. Phostrogen do one,
obtainable from most garden centres or sheds. Give it one feed now,
but it's getting a bit late in the season for nitrogen-rich feeds.
Give it some tomato fertiliser (potash-rich feed) in early August, to
encourage bud set for next year's flowers. Also give it a mulch over
the roots, say a two inch thickness of leaf mould, composted bark, or
peat.


--
Chris

E-mail: christopher[dot]hogg[at]virgin[dot]net

I put it in a tub with ( j.arthur bower) compost...I do feed it with phostrogen now and again. I think it must be the tap water that's doing it.. will do as you say..feed,etc.and stick to rainwater instead...(It has made new growth) many thanks..solaara

I put it in a tub with ( j.arthur bower) compost...I do feed it with phostrogen now and again. I think it must be the tap water that's doing it.. will do as you say..feed,etc.and stick to rainwater instead...(It has made new growth)... many thanks..solaara

On Tue, 12 Jul 2005 17:58:08 +0000, solaara
wrote:


I put it in a tub with ( j.arthur bower) compost...I do feed it with
phostrogen now and again. I think it must be the tap water that's doing
it.. will do as you say..feed,etc.and stick to rainwater instead...(It
has made new growth) many thanks..solaara


Was that compost specifically for ericaceous plants, or just a general
compost? If the latter, then that's probably where the problem lies,
as many of the general composts are slightly alkaline. If this is the
case, then it definitely needs ericaceous feed. Ordinary Phostrogen
won't do. It doesn't contain the chemicals necessary to compensate for
the alkaline soil.

But preferably under these circumstances, you should give it a dose of
sequestered iron and manganese. Murphy do it; it's called Sequestrine.
It comes in sachets of powder that you dissolve and water on to the
soil. Get it at any garden centre or in the garden department of a DIY
store. I'd treat it sooner rather than later, so that the rhodie can
take up the nutrients well before the autumn. One treatment should
last several months, but ideally you should re-pot into proper
ericaceous compost.

OTOH if it was in ericaceous compost in the first place, then as you
say, it's possibly hard water, and a standard ericaceous feed should
be sufficient in the future.


--
Chris

E-mail: christopher[dot]hogg[at]virgin[dot]net