Rootstocks and Flower Color

I was searching for a comparison of Rosa laevigata, R. banksiae and R. x fortuniana as rootstocks under varying conditions. I wasn’t able to find the info I wanted, but I did find something else that is just as interesting.

Communications in Soil Science and Plant Analysis (1979)
Effect of rootstocks on greenhouse rose flower yield and leaf nutrient levels
‘Carina’ rose was grown on seven different rootstock clones. These combinations were tested for effect on flower production and mineral content of the leaves when grown in fumigated ground beds in an evaporatively cooled plastic greenhouse. Plants growing on R. odorata ISU 5710-2 produced the highest flower yields followed by R. fortuniana and R. manetti while R. multiflora ISDU 62-5 produced the lowest number of blooms. Rootstocks caused large differences in the levels of some minerals in the leaves._ R. fortuniana_ caused a Mn accumulation that was five times the quantity developed by R. odorata but this did not seem to be related to flower production. However, R. odorata was a superior accumulator of K and under conditions of relatively low supply. R. fortuniana and R. odorata were good accumulators of N and K. These factors were related to flower yield.

I promptly remembered another note regarding nutrients and flower color.

American Rose Magazine 1(9): 14-15 (May-June 1934)
Fertilizer and Color
Dr. W. H. Brundige, TN
Four years ago I had a bed of forty-eight Red Radiances. From these I selected two bushes and used a commercial fertilizer—blood, bone, and potash in a ratio of 5-8-7. I used one pint to each bush on May 1, and such roses as they produced—dark red, with petals like velvet. The two bushes were entirely different from the others and bore the most beautiful flowers I ever saw.

It seems reasonable to suppose that a rootstock capable of providing the relevant nutrient might serve as well as fertilizer, which could explain (at least in part) the following:

American Gardening 14(9): 519 (1893)
Influence of Different Stocks on Marechal Niel Rose
JOHN DALLAS, Connecticut
Some years ago, in experimenting with different stocks in an endeavor to find the most suitable whereon to bud Marechal Niel, I was surprised at the different results attained, showing conclusively that the stock influences the color of the flowers. … The flowers of Marechal Niel were lighter in color on this stock [America] than on Cloth of Gold, which, but for one fault, is much the best stock of those under consideration. This fault is the inability of the stock to keep pace in growth with the Marechal Niel, causing a protuberance at the point of union, and finally resulting in a cankerous disease. The flowers from this stock were a very deep yellow, remarkably so when placed beside those from the Lamarque stock. … Ophier [Ophirie] is an old rose of a tan or copper color, short dumpy buds, but a fine cup shape when nearly open. … The petals of the Marechal Niel were deeply tinted with copper color half their length, the base of the flower a deep yellow, and the form of the flower was almost identical with Ophier. All the stocks under consideration had the same soil, equal light advantages, but yet produced decidedly different shades of yellow, and each retained these characteristics until they were destroyed.

Very intetesting topic!
I have even heard that different rootstocks can have an influence on the scent. Makes scense to me. A multiflora rootsrock will not go as deep as a rubiginosa rootstock for example. So that will also have its influence if nutrients are deep in the soil.
I believe there should be more research to rootstocks. Unfortunately, own root roses seem to be the future…
Also some rootsrocks die after 10 year while others can live forever, or ar least a lifetime…

Anyone on here who ia breeding for new rootstock varieties?

Wondering what “R. odorata ISU 5710-2” is…
Why is it unfortunate that own-root roses seem to be the future, if I may ask?

Most likely because in harsher, shorter, colder climates many own root types don’t push fast enough to perform as well as the same rose on a suitable stock.

I tend to agree with Kim.
Also, because if we only have own root roses, the heritage roses, who not always perform well on their own roots will be banished entirely from the market.
Don’t understand me wrong, I have nothing against roses on their own roots, unless they use a lot of environmentaly dangerous chemical hormones to get them rooted quickly.

I have been following up on this topic, and can only speculate at this point. But it does seem to me that when we are breeding from plants derived from four or five or nine different ancestral species, the kind of roots the seedlings have will be more of a crap shoot than flower form and color. In fact, it seems that some hybrids may be poisoning themselves because one parent is adept at sucking the last trace of mineral X from the soil, and the other parent finds the excess of X to be weakening.

Roots can exude various substances to modify the local pH, allowing them to liberate some nutrients in alkaline soil with organic acids, while other species raise the pH to avoid aluminum toxicity.

As for own-root roses being the wave of the future, I don’t see that happening where Fortuniana rules the roost. It would be silly to breed a whole range of alkaline sand specific cultivars, when most HTs and such can be budded onto Fortuniana for Floridians and West Australians.

Many of the “antique roses” will always be available, as long as theg ie is sufficient demand for them. Remember that budding is actually a fairly recent facet to roses. It wasn’t the preferred method (at least in the US) until the first decades of the Twentieth Century. Prior to that, virtually everything was introduced own root, so many of the old roses should be expected to grow reasonably own root. I would venture that more of the very early Twentieth Century HTs perform well own root than those produced in later decades because they were originally sold own root. Once budding became the accepted norm, who cared if it rooted or grew well that way? Most of the “novelties” would never have seen the sales floors had own root been the propagation method of the day as so few of them are decent on their own roots. And, as Karl suggested, there is likely to be quite a few extenuating circumstances preventing own root roses from being the only way they’re available. They may only be available from the large commercial producers on their own roots, but there will be the secondary producers for those markets. I frequently read from northern and eastern rose growers on the Internet rose forums how they prefer budded plants because own rooters simply don’t push strongly enough in their harsher winter, shorter growing season areas. As long as there are enough people willing and able to pay the prices for budded plants, they’ll still be around. Probably not as great a selection as we once enjoyed, but the latest releases and patented types which command the highest prices will still be offered.

In fact, back in the early 19th century, Chinas and Tea-scented roses were commonly budded because they were considered difficult to root as layers or cuttings. These were the original Tea-scented, by the way, rather than the later Tea roses that often had a good dose of Noisette and/or Bourbon in them. According to Loudon (1831) English nurserymen needed 2 seasons to produce a salable specimen. Vibert’s method was quicker.

Rosa banksiae was the preferred stock for Tea-scented roses; the yellow Tea-scented in particular.

Thanks, Karl. I guess that kicks the own root antique pushers in the slats, doesn’t it? I’ve battled the own root purists for a very long time concerning Teas, particularly the yellow Tea Noisettes. They CAN root, but it takes forever to produce a plant worth digging a hole for.

It is interesting to note that after slogging along for so long with the old and slow methods, English nursery folk and gardeners suddenly got creative with faster methods.

Gardener’s Magazine 6: 427-428 (1830) The following mode of propagation is easy and expeditious:— Put a plant or two into the hot-house in January or February, and there will soon be some young shoots: as soon as they have three or four leaves, take them off, no matter how tender or succulent, but never remove or shorten a leaf. Having prepared your cuttings, put them into sand, with a glass over them, in the same heat as the plants, and in three weeks they will be ready to be potted off. Thus continue taking fresh cuttings, or topping the cuttings already struck, till there are as many as you want. I propagated upwards of 100 plants in one season, from a small plant which only afforded three cuttings at the commencement.

Gardener’s Magazine 9: 524 (1833)
Mr. Brown is celebrated for having raised two roses of the Bengal kind, viz., Brown’s celestial and Brown’s superb. They are both roses which grow with great vigour, and they are peculiarly susceptible of training as pyramids. There is here a large stock of that scarce rose, the yellow Noisette, obtained by grafting portions of shoots, containing only a single bud, on stocks of Brown’s superb. This is an invention of one of the Messrs. Brown. The scion is not above an inch in length, and it is put on the stock, in the whip-grafting manner, close by the surface of the ground. The stock is of the wood of the former year, and the scion of the current year. Excellent and saleable plants are thus produced the very first season.

Gardener’s Magazine 9: 698 (1833) Chinese Roses may be propagated from single Buds, as Grape Vines are propagated.— The single bud, with a quarter of an inch of the stem both above and below it, is placed just under the soil, under a bell glass; the leafstalks and leaves standing upright as in a cutting. A single bud of Rosa semperflorens sanguinea was planted on July 26., and on Sept. 8. the bud had grown nearly four inches, and a blossom bud was formed. On Oct. 9. it was six inches high, and side shoots were being produced.
Charles M. Willich. London, Oct. 23. 1833.

And while I’m on the subject, I’ve found a couple of articles recommending that ‘Marechal Niel’ be double worked to avoid canker.

The Gardeners’ Chronicle 5: 782-783 (June 22, 1889)
A. D.
“Rosa” seems to have grave doubts as to the merit of double working, as I advocated, for Maréchal Niel, which has long been practised in our great nurseries. Very interesting and valuable results have flowed from the working of some strong grower on to a stock first, and then working a weaker grower of the same kind on to that; indeed, it is doubtful whether we have made half so much of the practice as it deserves. No doubt it requires the keeping of stocks a year longer in the nurseries, as the first scion must have a full year’s growth upon it ere that can be budded or grafted as the stock was before; but that objection by no means vitiates the practice, which is, without doubt, a good one. It may seem odd that the insertion of a germinator stem of some strong-growing variety should so materially influence both stock and graft or bud, but such is the case. In my own practice with Maréchal Niel, those which I have worked direct on to the briar, and on to the briar also through the intervention as primary stocks of Madame Berard and Lamartine, it should be understood that these strong growers had created the stock, practically long before they were budded with Maréchal Niel, and so far from these presenting a mere disc of wood in the stocks, they have stout branches of some 1, 2, or 3 feet in length, on to which the Maréchal is worked. Now, whilst in the case of the MaréchaI worked direct on to the briar, the stock has been but little swollen; the branch of the Maréchal, just above the junction, is treble the size, and very cracked or gouty. In the case of the double worked Maréchals, upon which the growth is always very robust, the original budded kinds swelled up the stocks thoroughly, and the whole growth, from stock to top, has grown simultaneously without cankering since the secondary budding of Maréchal Niel took place.

The Gardeners’ Chronicle. September 23, 1899. p. 250.
J. K., Wimborne
HAS any reader of the Gardeners’ Chronicle ever tried Maréchal Niel worked on Rose Devoniensis as a panacea for canker and loss of vigour after a few years cultivation under glass? If not, a market grower would recommend a trial being made, as with me the Rose has never yet shown a tendency to canker, but rather, as years go on, increase in vigour. There is much to recommend the use of Devoniensis as a stock, it being vigorous, with thick bark, and tenacious of life; the flowers, though good, are not so valuable as those of M. Niel, and it is not so profuse or regular a bloomer indoors. I have tried M. Niel on almost every kind of Rose, Manetti, de la Grifferae, Sweet Briar (which is a good one), Dog-Roses of the hedge-rows, and the less prickly one which grows in damp ground; Dundee Rambler, Hybrid Perpetual, Lamarque, Rêve d’Or, Cellini Forestier, and Gloire de Dijon, with interesting results; but the old Tea-Rose Devoniensis takes the palm for producing the weightiest blooms. I do not mean from Devoniensis on its own roots, but when worked on the seedling Briar or prepared Briar-stocks, which when established make robust growths, 10 to 12 feet long. From stocks from cuttings, excepting in the case of Gloire de Dijon, they do not reach that degree of vigour quickly, but the union with the Briar gives it forthwith.

I don’t know if the roots are relevant, but I got to thinking about a comment from Le Grice (1968).

"R. californica crossed with whites gave light browns and mauves and further crosses with lavenders gave bicolour browns with characteristic dominant slender but short growth and frequent bunched flowerings. This cross appears to give some stability in the browns."Le Grice: Unusual Colors (1968)

The flowers of R. californica don’t hint that the plant would contribute to mauve and brown shades. Or maybe the plant But you never know.

I used to hear the comment frequently made the plant they grew in Britain and used as Californica, wasn’t. What it was, I don’t know, but nothing in Californica points toward russets to my eye and none of the crosses I’ve had resulting from its pollen tended toward that direction.

I do recall such a discussion, a long while back. I think that one thread of it had Geschwind’s ‘Theano’ as the bogus Rosa californica of Europe.

That makes sense, in a way, if one regards hybrid seedlings of a species as “varieties”. Geschwind also listed the R. rubifolia (setigera) hybrids as “Rubifolias”. That (I think) is how ‘Souv de Brod’ came to be regarded as a seedling of R. setigara, rather than a second generation descendent.

If ‘Theano’ had ‘Crimson Rambler’ as pollen parent, the mauve and russet tones are not so surprising. But is the ‘Theano’ of today the same one Geschwind raised, and is it the R. californica used by Le Grice?

The influence of stocks is sometimes puzzling.

The Rural New-Yorker, 67(3063): 788 (Oct 10, 1908)
Mr. Sidney Hockridge, Redlands, Cal., writes:
Our soil is a red calcareous drift with perfect drainage, just suitable for strong-growing roses, while our hot Summers ripen the tender wood of the Cherokee so that nowhere else in this country is there to be seen such profusion of bloom, and travelers tell me that the Cherokee rose plants noticed in the Japan Archipelago did not approach in capacity for bloom those we have in our vicinity.

That is simple enough. Rosa laevigata thrives in heat. However …

Gardening 10(229): 198-199 (Mar 15, 1902)
Hybrid Stocks for Rose Propagation
Walter Van Fleet
…Perle des Jardins, budded on an established plant of the Cherokee rose, Rosa laevigata, is giving splendid blooms of almost exhibition quality, in a cold, damp house where five years’ effort with potted Perles on own roots and Manetti only resulted in a chance ‘bullhead’ once or twice a year. Further trials will be made with teas and hybrid teas on this stock.

There are plants that have shoots that thrive in heat, but have roots that prefer to been cool and moist. Gardenias, for example, and I think Clematises are in the same group.

And I suppose Hockridge’s plants were not blooming in the scorching heat, so the apparent contradiction may not be as extreme as I had thought.

BTW, I have been watching ‘Iceberg’ and ‘Burgundy Iceberg’ blooming profusely despite the 100+ F temperatures we’ve been “enjoying” in the past couple of months. The flowers don’t last very long, but they are quickly replaced.

Any suggestions for other varieties that can laugh at such miserable heat?

International Herald Tribune, Lynnie, Morey’s Pink, Bonica, Linda Campbell, Lauren, Sally Holmes…

I was searching for more of Dr. Van Fleet’s experiments with root stocks for roses. I found some interesting comments from him (1914) and one useful bit from J. T. Scott, Professional Florist and Commercial Plant Grower in N.Y. State :

Some Tea roses, particularly, have but one main root and a few straggling laterals, and every one who tries to transplant roses that have been growing in one place for several years knows what poor roots they have when lifted, and how hard it is to successfully transplant them. Because their roots are sparse and wiry they naturally need a heavy, stiff soil — or as we say in horticultural parlance, “a rose soil” — and heavy feeding with various fertilizers to bring out their best qualities.

This makes sense. I have learned from other reports that Rosa gigantea is at its best growing in clay over limestone. It is less splendid in gravel over granite.

Thanks for the suggestions. I do hope you can persuade ‘Morey’s Pink’ to complete its sporting to ‘Morey’s Red’. And then, perhaps, to ‘Morey’s Crimson’. After all, ‘Iceberg’ took a couple of baby steps before it got to ‘Burgundy Iceberg’.

Karl, I have encountered the red mutation on Morey’s Pink several times. I no longer grow it due to its not being any good for breeding with what I have tried it with. From its parentage, I would have expected it to have produced better results. I wanted it to, but it resisted, so it isn’t in my pot ghetto any longer.

The hidden traits of plants are often surprising. I would not look to Germany for a rose that tolerates 100+F temps, but there is ‘Iceberg’. And England is no higher on my list of places to seek heat tolerance, but there is ‘Int’l Herald Tribune’.

Such useful traits may be overlooked because no one bothers to check. For example, “White (85) discusses the possibility of the existence of genes for cold hardiness among tropical species and those having a southern range. He cites the case of a native Texas pecan that was found to be fully hardy in Canada. Three species of Iris native to Texas proved to be hardy in New York. Occasional mutations for hardiness in tropical plants are likely to be lost if there is no change of climate to give them selective value.”

The Yarnell paper I linked above makes another interesting point about sports.

The expression of a given trait may be influenced by varying environmental conditions. A mutation may occur at any time, but it is more likely to be discovered in an environment where the trait is most strongly expressed. “It might be added that the pink-blush grapefruit appears to develop better color in Texas than in Florida. It is likely that most of the bud mutations of this type have been brought to light in Texas on this account. There is no reason to suppose that the rate of mutation is any higher in Texas than in Florida”.

‘Iceberg’ was white in Germany and white in the U.S. But then it went to Australia where it sported to Pink, then Brilliant Pink and finally to Burgundy. Maybe it’s just a coincidence.