Friday, March 4, 2016

Making Babies

The word propagate is derived from Latin propagare, “to increase plants by cuttings,” from propages, a “cutting,” from pangere, “to fasten.” At Buchholz Nursery we also increase plants by grafting, and that word originated from Greek graphein, “to write” from the resemblance of the point of a cleft graft to a stylus. I don't know how the “graft” word also came to mean the acquisition of money, power etc. by dishonest or unfair means, but I have sure seen a lot of it. In any case we have finished our propagation for the “season,” a time-consuming process that began in July of 2015 and finished on February 28th of 2016.

For grafting we begin by rooting or purchasing rootstocks a year or two or three ahead, and then we “attach” the desired scions onto them; or for cuttings, we pluck current-year's plant growth from our stock trees and with the aid of a rooting hormone we then “stick” the cutting into a media consisting of pumice and peat moss and hope for the best. There is no way that I can adequately explain the procedures of propagation – the process that creates new plants which feeds my employees and myself – and to fully understand the fascinating details you would have to commit to five years of servitude at Buchholz Nursery. But at some point you will quit, concluding that you are smarter than old Buchholz, and then you will start your own plant nursery and...and then when you eventually grow old and tired and gray you will realize that a nursery is more easily gotten into than out of.

Maple grafts at Buchholz Nursery

Maples are always the first plants that we begin our grafting season with, and every year I'm anxious in the gut if the process will work. Even though it always has, I still worry and wonder if we'll be successful in the current season. A know-it-all ex-employee once told me that I worried too much; I replied that he didn't worry (or care) enough, and I turned out to be right because he was terminated at the end of the year. So yeah, I worry...that maybe the greenhouses will collapse from snow, maybe a new maple disease will appear, maybe our fertilizer was not formulated correctly and contains poison, maybe the grafters will suddenly forget to line up the cambiums etc. Well, those fears proved unfounded this year because the new growth from the maple scions is nicely progressing. The percent – the “take” – looks good, and in three-to-ten years from now the gardening public will have some nice plants to choose from.

Acer palmatum 'Golden Falls'

For the first time we grafted a handful of the Buchholz discovery, Acer palmatum 'Golden Falls', a yellow-foliaged selection that arose as a seedling from the weeping green A.p. 'Ryu sei'. About 500 'Ryu sei' seeds germinated and we potted all up, and then a year later we separated the 5% that displayed a pendulous form. All of them were green like the mother tree, except one that was yellow. Our 'Golden Falls' scionwood was not top quality, and I would have been happy if only a few survived so that I would have a backup, but to my surprise I saw that 100% made it. Maybe I should buy a lottery ticket too. Of course I am hoping that in the future I will find a red “Ryu sei;” then I would make a ton of money and you would find me on a beach sipping cocktails.

Acer macrophyllum 'Santiam Snow'

I see that a few grafts of the Acer macrophyllum 'Mieke' made it. Last summer I blogged about a new variegated “Big leaf maple,” 'Santiam Snow', which was introduced by Heritage Seedlings of Oregon. Green leaves are splashed with white, but I have yet to test it outside in full sun; but then I worry too much. A few days after reading my blog, friend Dave Kemper was driving down the narrow road to his property – Almost Paradise – a road he has taken thousands of times. Suddenly, for the first time, he noticed a macrophyllum branch also variegated with white. He brought me the wood which was mostly too big, but we were able to graft about ten sticks after scraping the scale off. Anyway, four are growing and I'll be sure that Dave gets one. The name of 'Mieke' is the nickname for Dave's wife, Marieke, a Dutch name.

Acer palmatum 'Killarney'

We didn't graft very many A.p. 'Killarney' because of limited scionwood, and there was limited scionwood because I've always considered the selection to be a “non-event,” so better to not have too many around. A few springs ago we shipped a good-sized tree to Amazing Maples in Washington state which I completely forgot about. Then in the fall I was on the Maple Society trip to Amazing Maples, where every maple in his collection was displaying fall color at the same time, which has never happened at my place ever. One plant had a wonderful pastel color that I had never seen on a maple before, and reaching for the label I saw that it was 'Killarney'. The way it was being grown – probably with less water than we use – allowed the fall color to prosper. Our plants, and especially those grown in a greenhouse, are so lush with new growth that I never saw what the maple was selected for in the first place. There is sparse information about 'Killarney' – who and where it came from – but I naturally assume that it was from the town of Killarney in Ireland, and the first place I saw it was at Wisley in England.

Acer pentaphyllum

We waited until winter to graft Acer pentaphyllum – the five-lobed maple – because the potential scionwood was so soft in summer. In January, 2016, we hooked about 200 pents onto the improbable rootstock of Acer rubrum. A. pentaphyllum is in the section Pentaphylla while the rubrum is in the section Rubra, and by appearance they are as different as cheese from chalk. Sadly, A. pentaphyllum is hardy to only about zone 8, or ten degrees above zero. I tested one outdoors – on rubrum rootstock – where the low was 5 degrees F. I waited...forever, because the species is notorious for leafing out late. By July I could see that the top was certainly dead, but the rootstock was sprouting from the base, determined to live. So my theory that a hardy rootstock might convey some hardiness to the top proved negative. I recall twenty years ago our state agricultural inspector was in a greenhouse checking on something, but he kept glancing further into the greenhouse, apparently obsessed with a lofty 12' pentaphyllum. He seemed troubled that I would so blatantly grow a marijuana plant out in the open. I didn't say anything until we progressed further, then I pointed out the Acer pentaphyllum, and I explained the name was due to the five lobes, and that it was perhaps the most rare of all maples with only twenty trees known in the wild. Inspector Gordon – who never knew much of anything about plants – was relieved and actually seemed fascinated with my maple story.

Davidia involucrata 'Sonoma'

Davidia involucrata 'Lady Sunshine'
Davidia involucrata 'Aya nishiki'

We potted some Davidia involucrata seed which originated from various 'Sonoma' trees, a cultivar known to bloom more early than the type, and the main reason is that Davidia rootstocks go for $6.50 each, and some even need an additional year before they are large enough to graft. At least the cultivars are fairly easy to take and there has never been a problem to sell them. It will take two years for the seed to germinate – if any do – and hopefully I can eliminate the expensive seedling purchase. The pride of our Davidia fleet is clearly 'Lady Sunshine', a selection from Crispin Silva of Oregon. 'Aya nishiki' is also popular, but I don't grow many because it burns in the Oregon sun. The straight species used to be an easy sell when I was early in my career, but no longer. Back to the cultivar 'Sonoma' which blooms early, it is a fantastic sight to see a six-foot branched tree with twenty large handkerchief bract-pairs hovering ghost-like in the foliage. In the Hillier Manual of Trees and Shrubs, I read that 'Sonoma' was “selected for its exceptional ability to flower as a young plant, sometimes after only two or three years.” That's not true at all – it was originally selected for its larger than normal bracts, with the early blooming an unexpected bonus. I have seen the mother tree at the Sonoma Horticultural Nursery in California, and while it was poorly sited and scraggly in appearance, the rest of the nursery was fantastic with numerous Japanese maples and Rhododendrons.

Cornus florida 'Autumn Gold' fall foliage

Cornus florida 'Autumn Gold' spring flower

I have lots of Cornus kousa cultivars, but only two of C. florida: 'Welchii', a variegated selection which burns in Oregon, and 'Autumn Gold'. I used to steer clear of C. florida due to its susceptibility to the anthracnose disease caused by the fungus Discula destructiva, but I like 'Autumn Gold' so much that we grafted a good number (onto C. kousa). Creamy white flower bracts greet the gardener in spring, followed by green foliage. In autumn the fruit is glossy red and the leaves turn a luminescent gold, and in winter the bright twigs range in color form yellow to orange. I got my start from the late Dennis Dodge of Connecticut when he offered to send scions. I didn't really want the florida, but I had just recently given him something and he wanted to “pay” me back, so out of politeness I accepted. Now I'm sure glad I did.

Thuja orientalis 'Franky Boy'

We grafted some Thuja orientalis 'Franky Boy'* on three-foot standards, and in four years from now the 'pops will form full heads, and they are quite unique and easy to market. They make for a Dr. Seuss type of creature. We also propagate it by winter rooted cuttings, and since 'Franky Boy' is still fairly new, sales are also good. Eventually it will grow into a broad, dense upright, and since we experienced a mild winter this year the thread-like foliage remained a pleasant green. In the 1984 Hillier manual (5th edition) orientalis is classified as a Thuja, but now it is placed in the monotypic genus of Platycladus. At some point I will issue orders to acknowledge the change, but that means my employees will be confused, besides that all of the labels will need replaced. When you look at the cones of the real Thujas, they are very different from Platycladus with its recurved hooks. Before the Thuja orientalis classification the genus name Biota was used. Biota now means the animal and plant life of a particular region, habitat or geological period, and the word is derived from the Greek biote for “life.” Interestingly the common name arborvita – which is actually spelled arborvitae – is Latin for “tree of life.” The word platycladus is from Greek platyclados meaning “with a broad stem.” The Chinese common name is baishu, but the genus is also native to Japan, Korea, Russia, and surprisingly there's a thousand-mile disjunct population in Ukraine.

*'Franky Boy' was a seedling of 'Elegantissima' raised by Frank Nursery in Austria.

Cupressus macrocarpa 'Greenstead Magnificent'

Early in my career I acquired a plant of Cupressus macrocarpa 'Greenstead Magnificent', a slow-growing blue form of the “Monterey cypress.” I wanted to propagate it but nothing rooted. Hmm, what rootstock could I use to graft it? When you consider a question like that you start by pondering what is related to it, not just scientifically, but also by appearance. I knew that C. macrocarpa was crossed with Chamaecyparis (at the time) nootkatensis and that resulted in x Cupressocyparis leylandii. Since I didn't have nootkatensis available, and since leylandii is not hardy in my market I tried Thuja orientalis because it's the rootstock I use for Chamaecyparis (Xanthocyparis) nootkatensis cultivars. Don't worry, you won't be asked to remember what I just wrote. Anyway, even with its hardy rootstock of T. orientalis...err, Platycladus orientalis, 'Greenstead Magnificent' is not fully hardy in Oregon. I planted one in the garden and it survived three winter but it succumbed in the fourth. I grow it for my Seattle and California markets, but one thing that displeases me is that Cupressus macrocarpa 'Greenstead Magnificent' takes a lot of time to write or type out, and try to fit that damn name on a label!

Cupressus cashmeriana

We grafted Cupressus cashmeriana onto Thuja occidentalis 'Smaragd', and have successfully done so for over twenty years. The graft union is perfect, but not so with T.o. 'Pyramidalis'; and it's a situation that I find odd, that if one cultivar is perfect, why is another one not? In any case, C. cashmeriana is now called by Hillier the “weeping cypress of Bhutan,” when in the 1980's it was “origin unknown,” and that “it has variously been regarded as a juvenile form of both C. funebris and C. torulosa.” It was introduced into England in 1862, and it was named cashmeriana because some were growing in Kashmir, India, around sacred places. Its origin is now known to be in Bhutan, and Debreczy and Racz in Conifers Around the World even report that “five tall trees of C. cashmeriana occurring on rocky marble slopes in northeastern Bhutan's Yangri Chu gorge were measured at an astounding 74-95m tall...making them among the tallest conifers in Asia – indeed, the world.” The earth has been highly scrutinized, so how could one of the tallest conifers in the world go unnoticed in Bhutan until recently? I love it when these types of discoveries are made.

Picea polita

This was the first winter that we grafted Picea polita in at least ten years. Sales were good in the 1980's and 1990's, with a Michigan customer claiming that P. polita was hardy for him. I find the spruce to be very attractive, but sales slowed to almost nothing, and maybe because customers found the sharp needles to be dangerous. The “Tiger-Tail spruce” was first described by Siebold when he was snooping in Japan, and it was J.G. Veitch who introduced it to England later in 1861. Once again we've had a name change, with Hillier listing it as P. polita in the 1980's, but in the 2014 edition (8th) it has been changed to P. torano. No explanation is given. Who is it that makes name changes without consulting with me, especially when you make my business more difficult? I don't even know what a torano is, and if you google it you'll get a famous cigar from the Casa Torano. So if there are any botanists in the Flora Wonder readership – and I doubt there are – get off your pedestal and answer me why polita was changed to torano.

Rhododendron orbiculare 'Exbury'

Rhododendron orbiculare 'Edinburgh'

Rhododendron orbiculare 'Edinburgh'

Rhododendron campanulatum ssp. aeruginosum

Rhododendron campanulatum ssp. aeruginosum

We grafted a couple of hundred Rhododendrons this winter, with the main goal of backing up my R. orbiculare 'Exbury' and 'Edinburgh', as I have only one plant of each. The rootstock wasn't perfect since I bought them from a Rhododendron nursery that grows them for a bushy form, not as rootstock, but the one-gallon pots were only $4 each. We also did another favorite, R. campanulatum ssp. aeruginosum, plus a few hybrids such as R. x 'Ever Red' and R. x 'Wine and Roses'. I won't describe any of them because I'm not really Rhododendron guy and I can't add anything new or interesting. Some have emailed that I never have, but they gutlessly sign off as Anonymous, the despicable cowards.

1 comment:

  1. many thanks for info about Davidia Sonoma.i hope one day visit your nursery !