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A happy grafter: Dryelle Pallaoro |
Greenhouse 12 is a propagation house, and it contains our winter-grafts of deciduous plants as well as various coniferous attempts. The hodge-podge ranges from maples to Magnolias, from Chamaecyparis to Calocedrus. The heater is set at 55 degrees F, although many days the temperature will exceed that. If it becomes too hot inside (in excess of 90 degrees F) we open up the house, otherwise we would be forcing new growth on the scionwood before its connection with the rootstock has been established. So, hot but not too hot.
At
the beginning of March, GH12 contains primarily sticks, pots and media (soil),
and there's really nothing fun to see. Now, at the end of March, I walk through
the house daily, and (for the past 34 years as well) I become giddy with the prospects
of many choice trees and shrubs to grow for future sales. One learns, though,
to not become too effusive, for swollen buds and emerging scion-leaves
might simply be the result of the warmth, and that the graft will ultimately
fail. In other words, don't count your propagules until June. Every year we
experience smashing successes as well as dismal failures, but the results are
never consistent from year to year. Usually I don't have a clue as to why a
successful crop one year can be followed by a poor "take" the next.
If a propagator is anything but humble, he or she is a fool.
There
is nothing magical about grafting; you merely slice the scion and rootstock to
match their cambiums*, secure the operation with a rubber band or plastic tape,
then stand back and hope for the best. Non-plantsmen or non-nurserymen are
invariably fascinated with the process, and they view me not as a technician,
but as some sort of floral wizard who has mastered the secrets to life. True,
it is stimulating to impress the novice with my copulatory prowess, but I never
want anyone to view my failures, also known as my dump pile.
*The cambium is
a layer of actively dividing cells between the xylem (fluid-conducting) and
phloem (food conducting) tissues. The grafter sees the cambium just past the
bark. The word is from Latin cambire, meaning to "change" or
"exchange."
Back
when we supplied thousands of grafts to other wholesale nurseries, an Oregon
company ordered 800 of just one item. We grafted 1,200 that winter, just to be
sure we could supply his 800, and then we planned to sell or grow on the
extras. Unfortunately (and mysteriously) this usually reliable crop of
Chamaecyparis nootkatensis 'Glauca Pendula' did not perform well, and we could
only supply him with 600 grafts. I then had to endure his lecture about how he
could "only do business with reliable sources." Sorry for just 600
out of 800, but realize that I was more unhappy about it than he was, for I
made no profit from the 50% effort. By the way, in 2009 he placed no order,
after consistently ordering in previous years, and has not bought a plant
since. I didn't bother to lecture him on my cost to have rootstocks produced
and ready to fulfill his custom order. Thus, this customer is officially classified as an ex-customer, in case he is still even in business.
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Cornus kousa 'Summer Fun' |
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Cornus kousa 'Summer Fun' in summer |
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Cornus kousa 'Summer Fun' in fall |
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Cornus kousa 'Ohkan' in June |
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Cornus kousa 'Ohkan' in October |
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Ginkgo biloba |

Ginkgo biloba
Ok,
let's step inside GH12, something I love to do on cold mornings. The soil is
fragrant in the warmth, and also fragrant is the foliage of Magnolias, Acers,
Fagus, Ginkgoes, Cornus etc., even though I can't really identify what smell
comes from a particular species. Visually, the predominant color now is green
for the majority of the rootstocks; but delightfully, nearly every other color
is sprinkled throughout with the emergence of the grafts. The variegated leaves
of Cornus kousa 'Summer Fun' and kousa 'Ohkan' are always pleasant. Employees
charged with pruning and thinning out the rootstock have an easy task, whereas
with the Ginkgoes, one must focus carefully on what to prune. Earlier I
mentioned to "stand back" after grafting, but that's hardly the case.
The aftercare, the "nursing" process, is often what determines a good
nurseryman from a poor one, and indeed, a profit from a loss.

Ginkgo biloba 'Jade Butterflies'
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Ginkgo biloba 'Marieken'
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Ginkgo biloba 'Marieken' |
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Ginkgo biloba 'Spring Grove' |

Ginkgo biloba 'Troll'
Our
gardens and greenhouses contain a large collection of Ginkgo cultivars, but
this year we narrowed our propagation to only eight cultivars: 'Jade
Butterflies', 'Marieken', 'Munchkin', 'Chase Manhattan', 'Snow Cloud', 'Spring
Grove', 'Troll' and 'Weeping Wonder'.* Notice that there are no variegated
selections, as I have finally grown weary of producing revertible plants. At
the liner stage most of our grafts look alike, so the employees must focus to not
mix them up. I don't know at what age you could eventually differentiate a
'Marieken' from a 'Troll' from a 'Spring Grove', and if ever mixed up in the
propagation house, the best solution would be to throw them all away, and
probably to eliminate the errant employee as well.
*Ginkgo biloba
'Tschi tschi' and some of the aforementioned are also produced via rooted
cuttings in summer under mist, and one learns which clones usually root better
than others. A fascinating concept is that the petioles themselves can strike
root, and I have seen a photo of this in an old conifer book. I have long meant
to try it myself, for I wonder if the rooted leaf will ever grow into a tree?
One can root, for example, the leaf-stems of Nandina, but they will not grow.
I
don't have a favorite Ginkgo cultivar – I like them all for their fresh green
leaves in spring, the deep greens in summer and the fantastic autumn yellows.
One that is different, though, is 'Munchkin', with its very small stature and
tiny button-sized leaves. It takes us at least five years to fill a one-gallon
pot, so it's my least favorite in
terms of profitability.
I
mentioned that we quit propagating variegated cultivars, unless Ginkgo biloba
'Snow Cloud' can be considered to be variegated; and well, yes...I guess it is.
Leaves are also undersized, and are longitudinally marked with faint
cream-white portions. Some leaves emerge without any green, and they are liable
to burn. My experience with this type of variegation is that the longer the
plant has been established in the ground, the less likely it is to burn, but
I've only grown 'Snow Cloud' for two years so far.
Pyrus
salicifolia is a species of pear
commonly called the "Willow Pear," native to the Middle East. The
small fruits are not edible and the species is grown only for ornament. I don't
know the origin of the species name, unless it is derived from Salix, Latin for "willow," but
salicifolia is also found with
Stachyurus salicifolia, Hebe salicifolia and others, and refers to long, narrow
willow-like leaves. The genus name Pyrus
is from Latin pirus, meaning
"pear tree." The common word "pear" is from the Germanic
word pera, and that from Latin pira, the plural of pirum. These words are similar to the Greek apios, which is of Semitic origin meaning "fruit," as the
verb pra means to "beget, to
multiply." The word parent is
from Latin parenteum, meaning
"father, mother, ancestor," from parere,
"to bring forth, give birth, produce."
In
any case we grow Pyrus salicifolia 'Pendula', a weeping haystack of a tree,
notable for silvery foliage. Flowers appear in spring, and they further add to
the dazzling display. Too bad the fruits are small, hard and astringent, for if
they were tasty every yard would contain a salicifolia 'Pendula'. This
excellent weeping cultivar received Britain's prestigious Award of Garden Merit
in 1969. In recent times, I acknowledge that it has apparently
fallen from favor, and I don't recall ever seeing it for sale in any
American garden center. I don't worry about that, because I'm confident that
all good trees have their due place and purpose. I am most pleased when I can
find an obscure species or cultivar and bring it back to market life.
Acer conspicuum 'Phoenix'


Acer davidii 'George Forrest'
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Acer davidii 'Hanshu suru' |
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Acer davidii 'Serpentine' |
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Acer rufinerve 'Kuro kogo beni' |

Acer pectinatum 'Mozart'
We
graft our Acer conspicuum 'Phoenix' in winter, and they are not difficult to
spot in GH12. In summer the wood is too soft (we find), and also for cultivars
of Acers tegmentosum, davidii, rufinerve and pectinatum. In Holland I have
visited various nurseries that don't get bothered by soft scionwood, but their
greenhouse conditions and their outdoor climate and their propagating brains
are much different from mine.
I
purchase rootstocks for our grafting of Fagus sylvatica cultivars (in 2
7/8" wide by 5" deep pots).
The grafts spend their first three weeks on our hot-callus pipe, then
return to GH12. By the beginning of April the scions begin to grow, and by the
end of April they have exploded with growth and demand to be potted up. Every
year I wonder why I graft so many, since the potting crew is overwhelmed with
shipping and other duties. There is always an April-to-June period when I wish
my crew size would double.
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Fagus sylvatica 'Bicolor Sartini' |

Fagus sylvatica 'Albovariegata'

Fagus sylvatica 'Marmo Star'
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Fagus sylvatica 'Nicole' |
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Acer palmatum 'Koto buki' |

Acer palmatum 'Koto buki'
Some
of the "European Beech" cultivars we produce are 'Bicolor Sartini',
'Albovariegata', 'Marmo Star', 'Nicole' and 'Aurea Pendula', with the latter
being grown by the largest number. The first four are all variegated, with
various portions and patterns of cream-white on green. I really should plant
one of each in a row to see which one performs the best. But even that might
lead to a dubious conclusion, since my experience with many variegated plants
is that no two look identical, and a crop of one cultivar might have some trees
more "colorful" than the others. With some cultivars there is no such
thing as a "clone," since every branch used in propagating can
potentially result in a different-looking tree. A maple collector once asked me
if I "had" Acer palmatum 'Koto buki'. My answer was "yes, and
no." My start was five scions, of which three lived. Seven years later,
one is very tall and vigorous (and hardly variegated), one is one-fourth the
size of the largest ( and the most colorful), and the third is in-between the
extremes. I only propagate from the smaller, most colorful plant, but not to
great success. So, is the largest tree 'Koto buki'? Well, yes and no; the labels
says yes, but I say no.
In
addition to the "Golden Weeping Beech" and the four variegated
selections, we also produce a cautious number of the "pillar"
cultivars. 'Red Obelisk' and 'Dawyck Purple' are two narrow forms with deep red-purple
foliage, while 'Dawyck Gold' is a narrow golden tree that performs well (in
Oregon anyway) in full sun. I never want to have too many of these fairly
common selections, but every year I sell out. But five or six years from now
they might be going for cheap at the box stores. The trend is that more and
more of the once proud – and frequently arrogant – large companies are dumping
their excess at the Lowes, Home Depots etc. They screw the general welfare of
the nursery industry as they flounder to stay afloat. They drag us all down
into the abyss of unprofitability... unless we come up with something new and
different. Shall I mention particular nursery names? I should, but I won't.
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Chamaecyparis lawsoniana 'Blue Surprise' |
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Chamaecyparis lawsoniana 'Drath Hexe' |
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Chamaecyparis obtusa 'Chirimen' |

Chamaecyparis obtusa 'Golden Pillar'

Thuja orientalis 'Franky Boy'

Calocedrus decurrens 'Berrima Gold'

Juniperus cedrus
While
I primarily think of GH12 for its contents of deciduous trees and shrubs, there
are some conifer grafts basking in the additional heat. Chamaecyparis, Thuja,
Calocedrus and Juniperus all perform better with extra heat in my experience.
"Needle" conifer grafts such as Picea, Pinus, Abies and Cedrus don't
need extra heat, and in fact I think they resent it. Their thermostat is set at
34 degrees F, and there's a huge difference in cost between 34 degrees and 55
degrees. Note the general difference between a needle conifer which shoots out growth
(in the cool house) and the GH12 stuff that grows by elongation. Understand I'm
not at all that smart about propagating, and I certainly don't recommend that
you copy me. All this talk about grafting is just me sharing my experience.
Just imagine how well off I would be if I really did know what I was doing!
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"Congratulations, Talon! You have been fruitful and you have multiplied." |