Hi,
I planted a rhododendron (dwarf rhododendron "baden-baden") in the
alkaline limey soil in my garden, before realising that these plants
hate lime. It was planted about 6 weeks ago and so far it is doing
fine. It had two flowers when I planted it, which have now fallen,
and although it has had no new flowers, it has loads of new shoots
growing. My question is - is it possible that the plant will do okay
here, or is it just a matter of time until the roots find the
surrounding alkaline soil and it starts to die off? should i move it,
or wait and see what happens. And what is the first sign of bad
health in this case... yellowing leaves? Any help appreciated,
Thanks
kamm

Usually chlorosis is seen first, that is yellowing of the leaf while the
veinery remains green. You should consider acidifying the surrounding soil.
You can use aluminum or iron sulphate, cottonseed meal, coffee grounds, etc.

Dave

"kamm" wrote in message
om...
Hi,
I planted a rhododendron (dwarf rhododendron "baden-baden") in the
alkaline limey soil in my garden, before realising that these plants
hate lime. It was planted about 6 weeks ago and so far it is doing
fine. It had two flowers when I planted it, which have now fallen,
and although it has had no new flowers, it has loads of new shoots
growing. My question is - is it possible that the plant will do okay
here, or is it just a matter of time until the roots find the
surrounding alkaline soil and it starts to die off? should i move it,
or wait and see what happens. And what is the first sign of bad
health in this case... yellowing leaves? Any help appreciated,
Thanks
kamm

I planted a rhododendron (dwarf rhododendron "baden-baden") in the
alkaline limey soil in my garden

As suggested, a localised area of more acidic soil is probably goinmg to work
better for you, though I have seen pictures of rhodos in the wild growing on
limestone outcrops, so the rules aren't hard and fast.
You may be able to get away with it the way it is, or perhaps with a periodic
Miracid treatment.

I got a question about making soil more acidic. Is it alright to use
cooking vinegar and dilute it to water rhododendron?

Thx,
Alex

"Bill Spohn" wrote in message
...
I planted a rhododendron (dwarf rhododendron "baden-baden") in the
alkaline limey soil in my garden

As suggested, a localised area of more acidic soil is probably goinmg to
work
better for you, though I have seen pictures of rhodos in the wild growing
on
limestone outcrops, so the rules aren't hard and fast.
You may be able to get away with it the way it is, or perhaps with a
periodic
Miracid treatment.

I got a question about making soil more acidic. Is it alright to use
cooking vinegar and dilute it to water rhododendron?

Would you like fries with that....?

I think that the only way to permanently imrpove the soil is to replace it in a
localised area or amend it with soemthing that will have a long lasting effect.


The suggestion of using acetic acid is a novel one, and I don't know the answer
to that.

If your rhodo starts to look chlorotic, I'd try the Miracid route first and
then if it still has problems, remove the soil immediately around the plant and
replace it with more acidic potting mix of some sort.

I suspect that any effect of vinegar (and probably Miracid as well) will be
temporary as long as the substrate is alkiline.

(kamm) wrote:
I planted a rhododendron (dwarf rhododendron "baden-baden") in the
alkaline limey soil in my garden, before realising that these plants
hate lime. It was planted about 6 weeks ago and so far it is doing
fine. It had two flowers when I planted it, which have now fallen,
and although it has had no new flowers, it has loads of new shoots
growing.

It will flower once each year on buds formed the previous fall and the
flowers last 2 to 6 weeks.

If your plant came from Europe, your Baden-Baden may be grafted onto
root stock of Cunningham White which is somewhat tolerant of alkaline
soil. If it is of American origin, it is just rooted from a cutting
and needs acidic soil. It is best to dig it up now and plant it
correctly. The most important factor in achieving vigorous growth is
an acid soil mixture high in organic content. Rhododendron and azaleas
need an acid soil with a pH of 5.0 to 6.0, well mulched with organic
material. Rhododendron thrive in a moist, well-drained, humus-filled
soil, enriched with peat moss or leaf mold. Prepare the soil by
thoroughly mixing equal parts of loam, coarse sand and ground oak
leaves or redwood before planting. Many commercial growers root
rhododendron and azaleas in pure sphagnum peat, or in a 50-50 mixture
of sphagnum peat and coarse sand or perlite. A favorite mixture on the
West Coast is 1/2 sphagnum peat and 1/2 ground bark dust, but in such
mixtures, plants must be fed regularly. My favorite soil mix is a
50-50 mix of peat humus and the natural soil. Soil around the
rhododendron's shallow roots must be kept cool and moist but well
drained. If the soil is too alkaline, acidity may be increased by
adding flowers of sulfur (powdered sulfur) or iron sulfate. I add 1
tablespoon of sulfur powder around the base of any plant showing signs
of chlorosis. Do not use aluminum sulfate. Aluminum can build up in
the soil to toxic levels eventually.

Because the roots grow near the surface, a bed prepared especially for
rhododendron and azaleas need not be more than 12 inches deep; deep
planting or too much mulch in the growing season keeps the roots from
getting the air they need. In fact, it is a good idea to set
rhododendron about 1 inch higher than they grew at the nursery.

Visit my Rhododendron and Azalea web pages at:
http://www.users.fast.net/~shenning/rhody.html
Also visit the Rhododendron and Azalea Bookstore at:
http://members.aol.com/rhodyman/rhodybooks.html

Cheers, Steve Henning in Reading, PA USA

In article ,
(Steve Henning) wrote:

(kamm) wrote:
I planted a rhododendron (dwarf rhododendron "baden-baden") in the
alkaline limey soil in my garden, before realising that these plants
hate lime. It was planted about 6 weeks ago and so far it is doing
fine. It had two flowers when I planted it, which have now fallen,
and although it has had no new flowers, it has loads of new shoots
growing.

It will flower once each year on buds formed the previous fall and the
flowers last 2 to 6 weeks.

If your plant came from Europe, your Baden-Baden may be grafted onto
root stock of Cunningham White which is somewhat tolerant of alkaline
soil. If it is of American origin, it is just rooted from a cutting
and needs acidic soil. It is best to dig it up now and plant it
correctly. The most important factor in achieving vigorous growth is
an acid soil mixture high in organic content. Rhododendron and azaleas
need an acid soil with a pH of 5.0 to 6.0, well mulched with organic
material. Rhododendron thrive in a moist, well-drained, humus-filled
soil, enriched with peat moss or leaf mold. Prepare the soil by
thoroughly mixing equal parts of loam, coarse sand and ground oak
leaves or redwood before planting.

Stop at this point.

Many commercial growers root
rhododendron and azaleas in pure sphagnum peat, or in a 50-50 mixture
of sphagnum peat and coarse sand or perlite.

"Correcting" soil with peat, sphagnum, or acidifying fertilizers does more
harm than good even in the short run. Field tests done in Edinburg have
shown that attempting to amend alkaline soils to suit rhododendrons fails
because the limestone is still there & the addition of acidifying chemical
fertilizers OR peat or sphagnum, merely causes mangenese to be bound to
the soil, & neither magneseum nor iron is accessible to the rhody
thereafter. Sulfer didn't bind the manganese but this "fix" was temporary.
Many rhodies did better in UNammended alkaline soils than in soils that
had been tricked out to give a neutral to acide pH reading despite the
continued presence of limestone in the soil.

Iron & magneseum reached the shrubs better if the alkaline soil was never
ammended. "Feeding" was best done by saving all the leaf-fall & prunings,
chopping them finely, & using them as mulch. Presumedly a mulch of conifer
needles would have the same effect though the Edinburgh trials didn't
study that. It is not done to change the pH but to get an accessible form
of manganese to the shrubs; if they can get those nutrients, it turns out
many rhodies tolerate more alkalinity than previously believed.

So in essence alkaline-hating rhodies simply should not be planted at all,
the corrective measures mainly increasing the chloratic outcomes. But
rhodies on the verge of alkaline tolerance can be adapted by feeding them
their own ground-up prunings & fallen leaves. Beyond that, most
fortunately, there are many genuinely alkaline-tolerant species-rhodies,
mostly small lepidotes, but also some that get to be the size of trees.
There are also the Inkarhos grafted rhodies developed specifically for
alkaline soils, & these are the big evergreen lepidotes that would
otherwise be alkaline-hating.

Here is a list of some of the species rhodies & azaleas that either
tolerate or prefer neutral-to-alkaline soils, some of these self-selecting
alkaline ridges as their primary habitat:

R. hirsutum
R. smsii
R. roseum
R. primuliflorum
R. telemateum
R. cuneatum
R. vernicosum
R. yungnanese
R. racemosum
R. taliense
R. rubiginosum
R. micranthum
R. orthocladum var orthocladum
R. kygwai
R. makinoi
R. myrtilfolium
R. opchraceum
R. bypoglaucum

I made that list some while ago when I first encountered the Edinburg
study, & added to it from the RHS and RSF lists of alkaline-tolerant
rhodies. Armed with such a list, anyone whose soils are not naturally
acidic can still have a broad collection of rhododendrons.

The Edinburg trials (& similar trials done in Germany) really indicate
that one great reason it has appeared that even slight alkalinity injured
most rhodies was because of the false belief that soils containing lime
can be "improved" by changing pH readings, when that just increases the
chloratic effect of the soil when manganese bonding irretrievably to the
limy soil, & enforcing a pleasing pH reason is simply not the end-all.
Some rhodies really are entirely unadaptable to any alkalinity, but as
many adapt as don't, & when the alkalinity increases, the vastly more
tolerant species rhodies or the Inkarho grafted elepidotes are the best
recourse. Amending soils to be at oddds with the greater environment will
not only have poor immediate benefit because of the bonded manganese, but
in the long run the greater environment will re-alkalinze even enormous
amended stretches of garden, & continuous re-acidifying increasingly
toxifies the ground (the harmful effects of artificially acidified then
re-acidified soils on camellias is well known, but the same thing happens
to rhodies just more slowly).

Such is my understanding from reading the papers. Luckily I live in a
naturally acidic-soiled part of the world & don't have to test those
tolerances myself.

-paghat the ratgirl

A favorite mixture on the
West Coast is 1/2 sphagnum peat and 1/2 ground bark dust, but in such
mixtures, plants must be fed regularly. My favorite soil mix is a
50-50 mix of peat humus and the natural soil. Soil around the
rhododendron's shallow roots must be kept cool and moist but well
drained. If the soil is too alkaline, acidity may be increased by
adding flowers of sulfur (powdered sulfur) or iron sulfate. I add 1
tablespoon of sulfur powder around the base of any plant showing signs
of chlorosis. Do not use aluminum sulfate. Aluminum can build up in
the soil to toxic levels eventually.

Because the roots grow near the surface, a bed prepared especially for
rhododendron and azaleas need not be more than 12 inches deep; deep
planting or too much mulch in the growing season keeps the roots from
getting the air they need. In fact, it is a good idea to set
rhododendron about 1 inch higher than they grew at the nursery.

Visit my Rhododendron and Azalea web pages at:
http://www.users.fast.net/~shenning/rhody.html
Also visit the Rhododendron and Azalea Bookstore at:
http://members.aol.com/rhodyman/rhodybooks.html

Cheers, Steve Henning in Reading, PA USA

--
"Of what are you afraid, my child?" inquired the kindly teacher.
"Oh, sir! The flowers, they are wild," replied the timid creature.
-from Peter Newell's "Wild Flowers"
See the Garden of Paghat the Ratgirl: http://www.paghat.com/

(paghat) wrote:

"Correcting" soil with peat, sphagnum, or acidifying fertilizers does more
harm than good even in the short run.

Actually the correct way to raise a broad spectrum of acid loving
rhododendron and azalea plants in an alkaline area is to use a raised
bed. You build up a raised bed with landscape timbers (nontoxic treated
wood or wood substitute). Then you get acidic or neutral soil and mix
it with good organic material. Since rhododendrons and azaleas have
shallow roots, if the raised bed is at least 10 to 12 inches high with a
gravel layer on the bottom, the alkaline soil will have no effect on the
rhododendrons and azaleas.

I was at the Rhododendron Species Foundation in Federal Way, WA, last
week. They had a large, over 20' tall, rhododendron they were
transplanting. The roots ball was less than 8 inches thick. They had
the roots sandwiched between two shipping pallets. That is the first
time I saw how really shallow rhododendron roots are on a very large
plant.

The alkaline areas that I plant in are near the foundation of my home.
The mortar in the stone walls leaches out and tends to sweeten the soil.
I compensate for this as needed by using sulfur powder when I see
chlorotic leaves. It lasts for many years between treatments. On new
homes, the effect be more transient. The soil is OK, but the salts that
are passing through it are the problem. Sulphur is able to handle that
problem.

--
Pardon my spam deterrent; send email to
Visit my Rhododendron and Azalea web pages at:
http://www.users.fast.net/~shenning/rhody.html
Also visit the Rhododendron and Azalea Bookstore at:
http://members.aol.com/rhodyman/rhodybooks.html
Cheers, Steve Henning in Reading, PA USA http://www.users.fast.net/~shenning

I was at the Rhododendron Species Foundation in Federal Way, WA, last
week. They had a large, over 20' tall, rhododendron they were
transplanting. The roots ball was less than 8 inches thick. They had
the roots sandwiched between two shipping pallets. That is the first
time I saw how really shallow rhododendron roots are on a very large
plant.


Steve - that was a fictolacteum - a picture of that very plant is at
www.rhodo.citymax.com at the bottom of the page! I was also struck by the
sight.

In article ,
"Stephen M. Henning" wrote:

(paghat) wrote:

"Correcting" soil with peat, sphagnum, or acidifying fertilizers does more
harm than good even in the short run.

Actually the correct way to raise a broad spectrum of acid loving
rhododendron and azalea plants in an alkaline area is to use a raised
bed. You build up a raised bed with landscape timbers (nontoxic treated
wood or wood substitute). Then you get acidic or neutral soil and mix
it with good organic material. Since rhododendrons and azaleas have
shallow roots, if the raised bed is at least 10 to 12 inches high with a
gravel layer on the bottom, the alkaline soil will have no effect on the
rhododendrons and azaleas.

Unfortunately if you lived in a part of the united states where the larger
environment is alkaline, so eventually will become that little hump. And
asthe Edinburg study showed, it really doesn't work to change the pH
reading of limy soils. They have to be grown in soils that never were
limy, OR one has to select lime-tolerant varieties and not alter the pH
reading at all.

I was at the Rhododendron Species Foundation in Federal Way, WA, last
week. They had a large, over 20' tall, rhododendron they were
transplanting. The roots ball was less than 8 inches thick. They had
the roots sandwiched between two shipping pallets. That is the first
time I saw how really shallow rhododendron roots are on a very large
plant.

I'm in the midst of moving five large old shrubs from a friend's house to
mine. Not 20 feet, but six to nine footers, very old. He didn't believe
we'd ever get them up, but I spaded a drip-line circle which missed all
the roots, then levered it upword with only the lightest tearing sound, &
voila, it was ready to move.

It definitely is surprising how little a root system they require to
sustain such a large shrub.

The alkaline areas that I plant in are near the foundation of my home.
The mortar in the stone walls leaches out and tends to sweeten the soil.
I compensate for this as needed by using sulfur powder when I see
chlorotic leaves. It lasts for many years between treatments. On new
homes, the effect be more transient. The soil is OK, but the salts that
are passing through it are the problem. Sulphur is able to handle that
problem.

You're speaking from the point of view of someone who luckily lives in a
region with naturally acidic soils. Even soils next to concrete walls, if
watered regularly, return to an acidic state, no artificial help required.
Concrete does NOT leech much alkalinity unless the concrete is losing
cohesion & turning to powder. It alkalinizes soil temporarily from watery
run-off when still curing (which for my hosue would've been nine decades
ago), but only if never watered AND sheltered under eaves so it never gets
rained on would it remain alkaline indefinitely. If your concrete
foundation is honestly re-alkalinizing your soil so that you have to
repeatedly add sulphur, your house is going to fall down into the powdery
residue of the dissolved concrete.

I works both ways: In a larger environment of naturally acidic soils,
alkalinized pockets will slowly re-acidify. You & I live in naturally
acidic soil environments, & any tinkering with pH readings we may do for
rhodies would be shooting toward what is normal, & we're not bucking
against nature. Someone who lived amidst naturally limy soils will really
have to select the lime-tolerant species-rhodies or grafted rhodies. As
the Edinburg study showed, attempting to acidify soils which are naturaly
limy locks in manganese so the shrubs become chloratic -- faster & worse
than if the pH reading had never been "corrected." I couldn't remember the
trial leader's name yesterday, but I looked him up, it was Professor David
Rankin, whose work in the last two years has corrected a lot of mistaken
thinking about growing rhodies in naturally alkaline environments. Part of
the reason it previously seemed so difficult was BECAUSE of the doomed
attempt to change pH readings before planting, resulting in
locked-manganese & doomed shrubs.

-paghat the ratgirl

--
"Of what are you afraid, my child?" inquired the kindly teacher.
"Oh, sir! The flowers, they are wild," replied the timid creature.
-from Peter Newell's "Wild Flowers"
See the Garden of Paghat the Ratgirl: http://www.paghat.com/