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Rhododendron and
Azalea News

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Winter 2007  Vol. 10  No. 4
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Plant Tips

Do you prefer organic fertilizer to chemical?

Alan Murray of the Victoria Chapter, Canada, has the answer for you with his special formula which has proven to be very effective when seen in his mountain-side garden in the Duncan area.

Use: 4 parts of alfalfa meal, canola meal, and blood meal.
        plus: 2 parts dolomite lime, and
        1 part each of rock phosphate, bone meal, kelp meal, and greensand.

This mixture should be applied once a year...only!

 


Is my rhododendron too leggy?

Many a member has asked this question at a chapter's meeting.  Some receive a good answer, others not too good a one to help them solve their problem.

Here's an answer from Cass Turnbull...in story form.

A brave...but unskilled gardener at the local pharmacy over-thinned a rhody on the grounds some 14 years ago.  Instead of looking like a nice little tree...the internal branches were so skinny and awkward that it looked like a collection of broken arms and legs.  And it has looked that way for most of the following 14 years.  This year I noticed for the first time that the canopy had finally grown back together, hiding the internal branch-work.  It looks okay.  But, no buds ever broke inside the shrub, all the new growth has been at the end.

too leggy...a cultural condition...

Many people have a skinny leggy rhody that is the result of bad culture...not bad pruning.  By this I mean, it was planted in too much sun, or too much shade (like between two buildings)...or there has been insufficient water...or too many weeds.  These are all 'cultural conditions' that have caused a problem as opposed to pest or disease problems.

solution...deadwood like crazy...

Like the pharmacy's rhody, there is not much help for them.  It is a good idea to try to eliminate the case of legginess...but it will still take a long time...and, perhaps, never look better. The best thing you can do is deadwood like crazy.

Get inside and remove each and every bit of it. And, the old yellow leaves, too!  On many branches you will find a tiny inch pointy peg of dead wood. It is the last bit of stem from an old bloom, still hanging on.  Take those off, too.  Remove any branches hanging on the ground. Then the shrub will look cleaner...and may be sort of artistic...or, at least, not so annoyingly awful.

And, I recommend you plant some lower-story plants to bring the eyes down.  Use sword ferns, epimedium, Lenten rose (Helleborus o.), and half-buried low maintenance rock.  Then your focus is shifted.

determine first if the rhododendron should be leggy...

If the cause of the problem is eliminated...like cutting down the Douglas fir nearby, or adding irrigation...you can try radical renovation.  If the cause is not remedied, you will simply kill the plant...or it will grow back leggy again.

And, take a moment to determine if your rhody is one of the species that is naturally open...leggy.  Most of these rhodies have large, long leaves.  If so, think of the one you have as a tree.

Good advice...think and study before making major aggression on your plants.

 

Develop a good weeding schedule

Dr. Rhody is asked this question:  Is there an easy way to remember the feeding schedule for the year?

several answers...

This question can be answered several ways.  It depends on the type of fertilizer you use and the soil conditions where you grow your plants.

I will refer to the fertilizer of choice for our immediate area...CENNCO - 20/12/8/8.  Sometimes referred to as Greer's Rhododendron Fertilizer or as North Willamette Mix.  This fertilizer has some immediately available nitrogen and time-released nitrogen plus some micro-nutrients that Rhododendrons need to look their best.

I would fertilize lightly, a small handful around the drip line, starting in early February and repeating every two months...February, April, June, August, and October...I believe this schedule works well for our area (Oregon).  We have lots of rain and, generally, porous soil conditions, large applications frequently are leached from the soil without being absorbed by the roots.  Frequent, light feedings prevent excessive leaching.

good to stop feeding for two months...

Some people believe our climate is such that we can feed all year around.  I personally prefer to stop during November through January.

Your plants will definitely survive without frequent feeding...but they won't be the best they can be!

-- Dr. Rhody

 


The gardener's creed

All of us have desires...wants...dream lists...when there's a enough of this and that.  Well, the Seattle Chapter put on black and white...maybe colored...the creed of a gardener.  It has appeared in other ARS newsletters.  Now, it is worth a repeat!  During these dull winter days, one can sit and watch it snow, the wind blow the bare tree limbs from side to side, and wish. Here's the creed...and it may be yours!

  1. I want it.
  2. I want it.
  3. I want it.
  4. If it will not grow in my zone...or is prohibitively expensive...I want it most of all.
  5. I am perfectly wiling to forgo any necessities of life, such as food for my child or pet in order to have it.
  6. I recognize my horticultural dependency.
  7. I recognize your horticultural dependency.
  8. I will willingly aid and abet your dependency, as you will mine.
  9. This makes us infinitely happy.
  10. Any money saved by virtue of comparison shopping equals found money and, therefore, is not counted as spending.
  11. If everyone else has it, I must have it, too.
  12. If I have planted everything that I have already purchased, I must immediately buy more plants.

NOW, recite your VISA number from memory.

 


Growing plants from seed

It is that time of the year when one receives one seed catalogue after another suggesting, buy me, buy me.  And, the grocery stores and the drug stores are selling packages of seeds...10 for a dollar.  In very way our senses are watered to buy more and more.  A friend told me,  remember the packages of seeds do not have as many seeds as they did a few years go.  You may think you are getting a bargain...but maybe not.

Ed Reilly, former president of the American Rhododendron Society, has some very valued suggestions on how you can start plants from seeds.  What fun to start looking at his suggestions on a cold winter evening, with beautiful music playing, a cup of hot chocolate, and a few chocolate chip cookies to top it off.

It's getting late already...so let's look at what Ed has to say.

Rhododendrons and azaleas are easily grown from seed!  Unless the parent plants are species from isolated areas, the resulting seedlings will exhibit much variability.  Unless you are interested in hybridizing and selecting new cultivars, use of seeds as a means of propagation should thus be limited to homogenous species plants.  Even then some physical differences will be evident.

Procedure...

  • Obtain clean seeds.
  • Prepare a sterile container at least three inches deep, with bottom drainage; size depending on how many seeds you wish to plant.
  • Fill the container to within inch of the top with a mixture of 40% perlite and 60% fine sphagnum peat moss.  This mixture should be moist...but not wet.
  • Level and firm the surface of the mix.
  • Spray the surfaced with Captan.
  • Sprinkle seeds thinly on the surface...do not water again.
  • Put plastic or glass over the container to make it moisture tight.
  • Place in a warm dimly lit area until seeds germinate.
  • Put under fluorescent...18 hours a day...at 70-75 F.
  • Anytime after true leaves have formed, harden the seedlings off by gradually opening the cover over the period of at least one week.  Water carefully as needed to keep moist.  Watering through drainage holes in the bottom is safest.
  • Transplant when to 1 inch tall to flats using 50% sphagnum peat and 50% perlite.  Lift under the roots and handle by a leaf.  Plant at same depth.  Water to settle in.
  • Water to keep moist...but no wet.  Fertilize with azalea food or other acid fertilizer once a month using half strength.  Always water at least once between fertilizer applications.  To slow growth and harden off, stop fertilizing and water less frequently.
  • Transplant as they become crowded.  Move to the cold frame after danger of frost has passed.

Keep the growing area clean to prevent damping off, water properly, and...success is almost assured!

 


Are there any white rhododendrons?

This question comes from frustrated artistic gardener.  She says she searches the sales and the garden centers...and cannot find a really good white rhododendron.

Again, Norm Todd comes up with an answer: She should not give up...but the cold hard fact is there are very few pristine white rhododendrons.  Most "white" rhodos have some color in the bud or in the throat or have some hint of shading in the petals.

White gives contrast, providing a foil for the bold strong reds and purples.  I think this particular questioner, however, wants a white border with no strong color present.

few suggestions may be of interest...

One or the purest whites is, befittingly, an old-timer...a hybrid from the mid-1850's...'Helen Schiffner'.  It is of medium stature with pretty good foliage...but is not seen very often these days, which is a shame.

A good start to the season and good for the front of the border is 'Snow Lady'.  Blooming in late February in local gardens, it covers itself with white flowers.  I think the chocolate anthers give depth to the plant.  It is wider than tall and its fuzzy, hair leaves look good all year.

'Senator Henry M. Jackson' is a wonderful pure white yakushimanum hybrid.  It is not easy to find.  Greer Gardens of Eugene, Oregon, list it.  Their catalogue gives useful lists...no whites...classify this one as white/blush.  The 'Senator's Wife' is also pretty good-looking.  She has...at least initially...a little color in her cheeks.  I was told that the original plant of 'Senator Jackson' was planted out in the grounds of the State Capitol in Olympia, Washington, but was stolen within the first few days of being on exhibition.

My best landscaper customer cannot abide the next plant...but I find it very useful for a sunny spot...'Dora Amateis'.  It is not too big...a lepidote with leaves 3 to 5 cm...and it does have a mauveish cast to the bud.  But, in full sun, it will look like a little igloo in April.

A most desirable dwarf, hard to find, is Peter Cox's 'Egret'.  Its flowers are tiny hanging bells.  The next is perhaps not the most shapely plant...but I wouldn't be without it...'Mildred Amateis'.  It is an interesting plant, as it is a cross between a toughie from the eastern U.S. and a semi-tropical Asiatic.  The latter...edgeworthii...gives it a delightful fragrance of nutmeg.  I have no 'nose' and would never make a wine taster, but 'Mildred' surely gives you a hit when walking past it in May.

There is a good selection of later blooming white of larger stature.  The easiest to find is probably 'Polar Bear'.  This comes from both of its parents...diaprepes and auriculatum.  Both are large plants.  Our auriculatum (the white form...it also comes in pink) was, we think, 26 years old before it had its first bloom.  The late Princess Abkhazi delighted in recounting how she waited 40 years before enjoying its August blooms.  For easy to grow late May bloomer, beloved by landscapers, 'Catawbiense Album' provides a good form all year.

the show-stopper...'Mi Amor'...

I admit...considering the number of rhododendrons hybrids there are...the whites are not very plentiful.  They do exist and are worth some effort to find.  I could not end without mentioning of one which not all of us can grow outside.  This one is truly spectacular...huge, lily-like trumpets of trusses of three of four with a little yellow in the throat, nicely textured leaves on an upright, tallish plant.  'Mi Amor' is a show stopper.  I have mine on a north-facing wall. I put it in the greenhouse last winter when the temperature went down to -9 C...the coldest we have had in our 30 years in this garden) and I am glad I did...it is now too big to move.  The buds are obscenely fat so am relying on global warming to let them burgeon open.

Thanks, Norm, for opening another 'world' to us.  For certain...many will be looking for another plant...come spring.

 

Something to think about...

God shall be my hope,
my stay, my guide and
lantern to my feet.

 -- Shakespeare

 

American Rhododendron Society
Executive Director: P.O. Box 525,  Niagara Falls, NY 14304
Ph: 416-424-1942   Fax: 905-262-1999   E-Mail: lauragrant@arsoffice.org
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