Bulletin of Botanical Gardens, 13: 199–207, 2004

OVERWINTERING OF HISTORICAL FROM THE COLLECTION OF THE BOTANICAL GARDEN OF THE POLISH ACADEMY OF SCIENCES IN WARSAW AFTER FROSTY WINTER 2002/2003

Marta Joanna MONDER

Botanical Garden – Center for Biological Diversity Conservation of the Polish Academy of Sciences, Prawdziwka 2, 02-973 Warsaw 76

SUMMARY them vanished in old, forgotten manor gar- dens and devastated nurseries. Ousted by The observations of 33 and varie- ever greater numbers of varieties, richer in ties of historical roses in Botanical Garden form and color, only small numbers of old after the long, frosty and snowy winter of roses have stayed in general cultivation and 2002/2003 indicate a considerable resistance these are enjoying their vintage status. Many to frost in most of them, park roses in particu- of them show high resistance to frost and lit- lar, which is a very important aspect of tle proneness to diseases. Although most of cultivation in the areas with reduced cultiva- them flower once only, their flowering is tion expenses. Damage was not noticed or was abundant and long and the flowers give off minimal to the park roses descending exquisite smell. Their thorns, shoot color, from Rosa x damascena Mill, Rosa alba L., leaves and fruits are often an additional orna- Rosa x centifolia L., Rosa moyesii Hems. & ment. Wils. Insignificant frost damage to Bourbon, For over 20 years now the varieties and Portland and Hybrid Perpetual didn’t have any species of the past have been growing in negative impact on their development and importance and are planted in parks and gar- ornamental qualities in vegetative season. The dens, particularly in those of period character, most severe damage was caused to climbers or as low-requirement in naturalistic and ramblers and these suffered the heaviest foundations along with other ornamental loss of ornamental value. . They have been arousing the interest of plant lovers, nursery people and gardeners. Key Words: old roses, Rosa L., shrub roses, In a few nurseries in Poland a small number of frost resistance. old varieties are being reproduced and demand is growing along with the trends from INTRODUCTION other European countries. The rising interest is confirmed by breeding direction in many At present the collection of roses in foreign breeding companies. Varieties such as Botanical Garden numbers over 386 rose English Roses, (David Austin Roses), varieties, including 77 species and varieties Romantica (Meilland), Renaissance (Poulsen of roses now rarely grown. What was recog- Roser Aps), Rigo Rosen and Märchen Rosen nized as historical roses were the species and (W. Kordes Söhne) have appeared, which are varieties grown in the early stages of the cul- similar to old roses but have new colors, tivation of this species as well as the varieties heightened resistance to diseases, recurring which appeared in the 19th and early 20th cen- flowering and better growth. Unfortunately, tury. Many varieties which were cultivated most of them display significantly worse then passed out of all knowing but a consider- resistance to frost. able part survived in rosaries, botanical After the severe winter of 2002/2003 the col- gardens’ collections and old parks mainly in lection underwent frost resistance observations France, Britain and Germany. In the Second aimed to find out more about historical roses World War Poland and after the war most of and their application potential.

199 Marta Joanna Monder

METEOROLOGICAL CONDITIONS their crowns covered with straw or paper (table IN WINTER 1). In the preceding years (1999–2001) the bor- ders had been littered with bark. The winter of 2002/2003 came early and was In spring frost damage to shrubs was esti- long and frosty. The previous two winter sea- mated and the number of shrubs damaged by sons had been much milder. Mean month tem- frost and those which needed to have their peratures and precipitation from January to shoots cut out was expressed in percentage and September in 2003 and in 2000-2002 in the losses were assessed according to the scale Botanical Garden are shown in Fig. 1 and 3. by ¸ukasiewicz (1992) for deciduous plants, Mean 24-hour air temperature is shown in omitting 2, 8 and 9 as they were not applicable Fig. 2. Minimal and maximal temperatures in in this case. Meteorological Station in Agricultural 0 – no damage to plants University in Warsaw in October 2002 – April 1– darkened vascular bundles on the shoots 2003 are shown in Fig. 4. October 2002 was but the buds develop cold and in early November 24-hour mean tem- 2– flower buds frozen peratures happened to be below 0°C. In mid- 3 – leaf buds frozen December –17,3°C was recorded and a few 4 – one-year-old shoot tips frozen days later –19,8°C. The lowest 24-hour mean 5 – one-year-old shoots frozen or with living temperature was recorded in January (–22,5°C). bases only In March and early April temperatures tended 6 – two and more-year-old shoots frozen to be below or around 0°C. All winter long 7– shoots frozen to the ground (snow) but the there was a thick snow cover although the 24- undamaged parts (bases of shoots or roots) hour temperatures were above 0°C at times grow new shoots (Fig. 3). At the beginning of April, after the 8 – cracked trunks thaw and the melting of snow cover and a dozen 9 – trunk or branch rot of warm days with the temperature above 0°C 10 – the entire plant frozen (no sings of regene- a few-day cooler period returned and the tem- ration). perature fell below 0°C. In the second half of Additionally, it was noted how high from the April it warmed up fairly quickly and it was ground the damaged shoots needed to be possible to begin the uncovering and cutting of pruned. At the beginning of May the selected shrubs (Fig. 2). varieties had the number and length of their new growths measured. In vegetative season MATERIALS AND METHODS the flowering time of the shrubs was noted.

To estimate resistance to frost, several-year- RESULTS AND REMARKS old shrubs of 33 historical rose varieties from the collection of Botanical Garden were used Polish winters happen to be very frosty and (all the shrubs of the variety examined were rose shrubs, particularly more sensitive varie- used, which means that in some cases the obser- ties can be badly affected or even die. The vations were done on single shrubs) (table 1). least resistant to frost are thea hybrids, while The shrubs came from various sources and were floribundas and polyanthas are less susceptible. budded on various rootstocks (Rosa multiflora, After the severe winter of 1986/87, 260 roses Rosa rubiginosa, Rosa laxa, Rosa canina). were badly damaged, which accounts for 76.9% Prior to the frosty winter the shrubs had been of the 338 thea hybrids and floribundas tested in treated with a small dose of mineral manure the collection of ground roses from the Division with microelements (1–2 kg/100 m2 of of Ornamental Plants of Agricultural Academy “Azofoska”) and after flowering with a liquid in Poznaƒ. Among the varieties which can be fertilizer “Florogama” into soil and “Ekolist” regarded as resistant, provided the shrubs are onto the leaves, the dose as prescribed by the covered with a small pile of soil, there are old producer. For the winter 2002/2003 most roses varieties, which makes them noteworthy again. were covered with a small pile of soil to protect (Czekalski et al. 1990). Most roses, even if only their basal parts up to 25–30 cm. A few had slightly damaged by frost need to be pruned to

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Marta Joanna Monder 2 Time flowering of the first 11 01 – uncovered 25.05–15.07 – uncovered 20.05–7.07 – covered with soil 18.06–16.07 [cm] per shoot ground shoots shoots to shoots in shrubs damage damage* from the of young of young collection of planting of of frost of frost of cutting number length spring 2001 1 slightly 4 normal cutting – spring 1998 1 slightly 0 normal cutting – spring 1998spring 1998 1 1spring 2000 slightly 1 slightly 0 slightly 0 normal cutting normal cutting 5 – – normal cutting 13.7 – 13.3 uncovered uncovered 25.05–17.07 25.06–25.07 autumn 2001 2 slightly 4 normal cutting 113 5 11.1 uncovered 5.06–18.06 autumn 2001 1 slightly 0 normal cutting 76.5 21.3 uncovered 25.05–17.07 autumn 2000 2autumn 2000 1 slightly slightly 4 normal cutting 0 205.0 normal cutting 13.2 – covered with soil 1.06–10.07 11.6 uncovered 1.06–20.07 R. laxa R. laxa R. laxa Rootstock Year Number Percentage Scale Height Average Average Note R. multiflora R. multiflora R. multiflora R. multiflora on own roots autumn 1999 3 slightly 0 normal cutting – 19.5 uncovered 25.05–17.06 , L., L., L., L. Hems. on own roots spring 1998 3 slightly 0 normal cutting – 8.9 uncovered 25.05-10.07 ‘Alba’ Thunb. Thunb., no data spring 1998 3 slightly 4 normal cutting 22.5 23.4 uncovered 1.06–5.07 Thunb., Thunb., and muscosa 1937 Origin grower muscosa Vibert 1830 Vibert 1830 Laffay 1840 Laffay 1863 Waterer 1898 var. de Goey 1918 R. x centifolia R. laxa Saunders 1900 Rosa x alba Rosa x alba L., on own roots autumn 1999 4 slightly 0 normal cutting – 14.6 uncovered 25.05–7.06 wprow. w 1858 Rosa gallica Rosa gallica Rosa gallica Rosa x centifolia R. laxa Rosa beggeriana Boiss., Wasastjärna Rosa rugosa Rosa moyesii et Wils., P. Dot 1927 Rosa rugosa Rosa rugosa Rosa rugosa 1234567891 Evaluation of damage to historical rose shrubs caused by frost 2002/2003 Variety eux ï F. J. Grootendorst Agnes Mrs Anthony Waterer Rugeaux du Japon Cardinal Nevada de Richelieu Cama Polstjärnan Shailer’s White MossHenri Matin var. Belle Hermine Hurdalsrosen Maiden’s Blush Table. 1.

204 Overwintering of historical roses from the collection of the Botanical Garden of the Polish Academy – 2 11 paper, diseases flowering damaged on no flowering no flowering enough, poor poor flowering poor flowering shoots diseases regenerates well regenerates well, by shoot diseases, by shoot diseases, damaged by shoot 01 – the shoots damaged 29.06–20.07 – covered of paper 15.06–29.07 – the shoots damaged 25.06–20.07 – covered with paper, – – covered with paper, – – – – – – 40 40 40 40 40 surface of ground 7 5 to 10 33.0 13.6 no flowering 6 6 7–8 buds 16.0 7.5 70% the shoots 15.06–15.07 6 6 normal cutting 101 3 20.4 uncovered 1.06–5.07 6 4 normal cutting 21.4 6.8 covered of soil 30.05–1.07 6 3–4 buds, 10cm 35.5 10.9 covered with 1.06–20.07 4 normal cutting 205.0 13.2 covered with soil 5.06–2.07 6 7–8 buds6 23.4 20.0 70% of the shoots 15.06–10.07 6 7 cutting under the 11.5 3.3 regenerates well – 85 60 70 50 50 60 70 90 10 70 60 60 95 spring 1998 4 spring 2001 1 spring 2000 1 spring 1998 4 spring 2000 1 spring 2000 1 autumn 2000 1 autumn 1999 5 autumn 2001 2 autumn 2001 5 autumn 2000 3 ‘ autumn 1999 4 no data spring 1998 3 1902 Robert 1860 Robert, 1868 Desp , Moreau et Robert 1874 Rosa multiflora R. laxa Crép., van Fleet Schmid’s Ideal’ West., Moreau – Desp., Bizot 1868 Rosa wichuraiana R. multiflora Rosa wichuraiana R. canina Rosa wichuraiana R. laxa Rosa wichuraiana R. laxa Crép., Walsh 1909 Rosa x portlandica R. multiflora Rosa x portlandica R. rubiginosa Rosa x borboniana Rosa x borboniana R. multiflora Rosa x borboniana R. multiflora Rosa x borboniana R. multiflora Rosa x borboniana R. multiflora Crép , Barbier 1906 Crép , Barbier 1903 Desp., wprow. 1842 Rosa x wichuraiana R. laxa Crép., van Fleet 1902 Desp., Margottin 1851 1234567891 ois Pillar Excelsa Pillar American Comte American de Chambord West., Moreau – Jacques Cartier de Féligonde Thunb., Turbat 1916 Juranville Ghislaine Drouhin Louise Odier Commandant Beaupereire Fran ç Zéphirine Variegata di BolognaPrince Charlez Desp., Bonfiglioli 1909 Léontine Gervais

205 Marta Joanna Monder 2 11 regenerates, damaged on frozen, 1 poor lack flowering shoot's diseases 01 – 3 shrubs were – of ground the surface 4 normal cutting 26.7 10.8 covered of soil 30.05–1.07 4 normal cutting 13.2 13.1 covered of soil 3.06–10.07 4 normal cutting 116.0 8.0 10% the shoots 25.05–7.06 4 normal cutting 336.0 10.2 uncovered 25.05–7.06 6 6–8 buds, 30 cm 15.0 18.9 covered of paper 10.06–10.07 70 50 10 30 60 90 7/10 cutting under – autumn 1999 4 autumn 1999 4 autumn 1999 4 slightly 0 normal cutting 45.0 12.1 covered of soil 30.05–1.07 autumn 2000 2 autumn 1998 4 R. multiflora on own roots autumn 1999 7 R. rubiginosa , on own roots autumn 1999 6 slightly 0 normal cutting – 8.8 uncovered 15.05–5.06 var. on own roots autumn 1999 4 Rehder Verdier 1863 Lambert 1901 ‘Schmid’s Ideal’ Rosa multiflora R. multiflora persiana Rosa foetida Rosa x harrisonii Rosa x stenbergii Mill., upr. w Iranie Rosa x damascena R. rubiginosa Rosa thea hybrida , wprow. XIX wieku Pernet-Ducher 1890 Rivers, wprow. 1830 Rosa hybrida bifera , Rosa hybrida bifera, R. canina Thunb., Schmidt 1909 1234567891 Mme Victor Verdier Frau Karl Druschki Rose de Rescht Persian Yellow Poppius Harisons Yellow Mme Caroline Testout Veilchenblau scale of frost damage for deciduous plants by ¸ukasiewicz (1992) *

206 Overwintering of historical roses from the collection of the Botanical Garden of the Polish Academy

In 2003 warmer days came around mid- REFERENCES April, which delayed vegetation. In May the greatest number of shoots were observed in Czekalski M., Oszkinis K., ˚y∏a S. 1990. park varieties e.g. ‘Mrs Anthony Waterer’, Uszkodzenia mrozowe ró˝ powsta∏e podczas ‘Harrisons Yellow’, Variegata di Bologna zimy 1986/1987. Ogrodnictwo 1-3: 44-45. while the smallest number of shoots were Grimm H. i W., Mielke H., Vemmer E. 1996. observed in more intensely pruned Hybrid Rosensammlung zu Wilhelmshöhe. Rosenkreis Perpetual, Portland, Hybrid Tea, that is in the des Vereins Deutscher Rosenfreude e. V. und group characterized by lesser growth intensity Verein Roseninsel Park Wilhelmshöhe. Kassel. and tillering and those roses which were badly Gustavsson Lars-Ake 1999. Rosenlexikon. damaged by frost. The same applies to the Rosinante Forlag A/S. Kopenhaga. length of young shoots that grew in spring Jerzy M., ˚y∏a S., Czekalski M. 1992. Ró˝e. (Table 1). The shrubs of all the varieties except PWRiL, Warszawa. ‘Zephirine Drouhin’ and ’Veilchenblau’ grew ¸ukasiewicz A. 1992. Zahamowanie rozwoju pà- intensively. ków u niektórych drzew iglastych po surowej Late spring affected flowering as well, zimie 1986/1987 i wynikajàca stàd potrzeba which started later that year and was therefore uzupe∏nienia skali przemro˝eƒ u drzew i krze- shorter by a few days for the varieties flowering wów. Biuletyn Ogrodów Botanicznych, Mu- the earliest (early May). The varieties which zeów i Zbiorów, vol.1: 53-57. failed to blossom that year were: ‘Zéphirine Sieber J. 1989. Rosen für den ländlichen Drouhin’, ‘Excelsa’, ‘François Juranville’, Siedlungsraum. Deutsche Baumschule, 9: 446- ‘Léontine Gervais’, ‘Veilchenblau’ (Table 1). 447. These blossom on two-year-old or older shoots, Wojdy∏a A., WiÊniewska-Grzeszkiewicz H. which had been cut out as a result of frost 2000. Wyst´powanie zamierania p´dów na damage. ‘Zéphirine Drouhin’ had some flowers gatunkach i odmianach ró˝. Ogólnopolska late summer (it blooms once only, in late June), Konferencja Ró˝ana „Ró˝e w szkó∏ce i pod which didn’t have any ornamental value. os∏onami”, Skierniewice, 47-51.

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