American Rose Annual 41:44-48 (1956)
Perpetual Flowering Roses
NORMAN YOUNG
HORNING, NORFOLK, ENGLAND

*After five generations, the proportion of the original parent present in the offspring is theoretically 1/32; and since R. moschata has only 14 chromosomes, it is rather more than an even chance that a representative of the fifth generation will contain no trace of its moschata ancestry whatever!

It is fashionable nowadays to cavil at the use of that expression "perpetual flowering," on the ground that it is inaccurate. If it comes to that, a great many technical terms are inaccurate when literally interpreted; my "eight-day" clock, for example, actually runs twelve days at a single winding, while my "waterproof" coat would make a very inadequate protection for a deep-sea diver. And as many of the cavillers are quite happy to describe as a "Hybrid Musk," for example, a rose which is five generations removed from the original Rosa moschata* I do not think we need take their objections very seriously. So far as I am concerned, a perpetual flowering rose is one which displays more than a single burst of flower in the year. And with the object of finding out just what this property implies in our gardens, I have kept a careful record of the flowering periods of a typical selection of varieties in my own garden throughout the past season.

It was hardly practical to maintain my records right up to the falling of the very last rose in the garden, since given a mild autumn this might have meant going on to the end of the year or even later. My own feeling was that after the end of October the virtue has gone out of the rose-beds, and a plant which continues to flower is simply wasting energy which could have been turned to better account in producing more or earlier flowers; and I accordingly fixed the 31st of October as an arbitrary closing date for my investigation. So far as this year was concerned, Providence endorsed my decision by sending a hard frost on the night of the 31st, followed by an even harder one the next night, which effectively settled the hash of all but the hardiest winter bloomers and in a brief thirty-six hours converted my garden from a slightly dishevelled paradise to a gloomy wilderness, in which even Moore would have found it difficult to sentimentalize over the Last Rose of Summer. There remained the question of how to treat those roses which, though not in flower on the last day, yet still carried buds which might -- or might not -- open. In the long run I thought it fairer to regard them as having finished their flowering season with the fall of the last flower before the closing date.

There were actually two quite separate factors that I had to take into account. On the one hand, the aggregate length of a rose's flowering periods is a measure of virtue in itself, and to some gardeners this might seem the more important consideration. On the other hand, continuity of flowering is also (and to my mind equally) desirable. To try and suit all tastes, I have arranged my examples in two different orders of merit, based on each of these two factors; in Table III I have combined the two, basing the final order on a figure of merit, obtained by multiplying together the points obtained under both heads.

The choice of examples that I have given was not entirely haphazard. I have excluded the results obtained from any rose which, for one reason or another, did not seem to me to have done itself full justice; to this extent, then, the list may be taken as composed of the best results chosen from a list perhaps twice as long as that shown. On the other hand, I took no special pains to ensure specially good results; the long dry summer induced me to feed my roses rather less than usual (though I should perhaps explain that as my garden is sited on the margin of a river, there was at no time any serious drought). None of the plants tested was more than three years old; Will Scarlet, Damascena N.L. 849 and Reine des Violettes were all in their first year, yet gave a performance deserving of record. I should perhaps add that my soil is a heavy, damp clay, mixed with peat, and since the river rises in chalk country, it is definitely alkaline. For many weeks in the preceding winter it was waterlogged, and for a full week it was actually under several inches of water -- and water which contained a measurable quantity of salt! Strangely enough, no apparent harm resulted.

The results, I think, speak for themselves. While there are some significant reshufflings between Tables I and II, per haps the most striking thing about them is their general similarity. There is no obvious reason why length of flowering season and continuity of flowering should go together, yet there is a distinct tendency in this direction. I found no tendency whatever to produce an early burst of flowering followed by a long rest until the autumn; of the five varieties which achieved only two flowering periods in the time, all had started on their second burst before the end of August. Rubaiyat got its second wind at the end of July. The figures followed by a plus sign are those where the plant was still actually flowering on the closing date; about half of the others were carrying buds at the end, though many of these were blasted by the frost.

TABLE I. LENGTH OF FLOWERING SEASON.

  Variety Class Total
season
Days
flower
1. Zephirine Drouhin Bourbon 137+ 110+
2. Will Scarlet HMs 112+ 108+
3. Cl. Lady Hillingdon CT 121 107
4. Independence Fl 112 105
5. Peace HT 125+ 100+
6. Sultane HT 131+ 99+
7. Betty Uprichard HT 132+ 98+
8. Cl. Etoile de Hollande CHT 138+ 95+
9. Irene Churruca HT 105 90
10. Damascena N.L. 849 Damask 94 88
11. Lady Sylvia HT 113 85
12. McGredy's Yellow HT 106 84
13. Mme. Charles Rouveure HT 115 80
14. Mev. G. A. van Rossem HT 132+ 76+
15. High Noon CHT 92 76
16. Reine des Violettes HP 93 71
17. Shot Silk HT 96 69
18. Rubaiyat HT 77 64
19. Talisman HT 95 64
20. Charles Mallerin HT 87 56

TABLE II. CONTINUITY OF FLOWERING.

 

Variety

Percentage of
 flowering days

1. Will Scarlet 97
2. Damascena N.L. 849 95
3. Independence 94
4. Cl. Lady Hillingdon 89
5. Irene Churruca 86
6. Rubaiyat 83
7. High Noon (Cl.) 82
8. Zephirine Drouhin 80
9. Peace 80
10. McGredy's Yellow 79
11. Reine des Violettes 76
12. Sultane 76
13. Lady Sylvia 75
14. Betty Uprichard 74
15. Shot Silk 72
16. Mme. Charles Rouveure 70
17. Cl. Etoile de Hollande 69
18. Talisman 67
19. Charles Mallerin 64
20. Mev. G. A. van Rossem 58

TABLE III. COMBINED ORDER OF MERIT.

  Variety

Figure of Merit

1. Will Scarlet 106
2. Independence 99
3. Cl. Lady Hillingdon 95
4. Zephlrine Drouhin 88
5. Damascena N.L. 849 84
6. Peace 80
7. Irene Churruca 77
8. Sultane 75
9. Betty Uprichard 73
10. Cl. Etoile de Hollande 66
11. McGredy's Yellow 66
12. Lady Sylvia 64
13. High Noon (CL) 62
14. Mme. Charles Rouveure 56
15. Reines des Violettes 54
16. Rubaiyat 53
17. Shot Silk 50
18. Mev. G. A. van Rossem 44
19. Talisman 43
20. Charles Mallerin 36

That a so-called Hybrid Musk and a Floribunda should head the final list will occasion no surprise, but that the third place should go to a Tea rose, and a climber at that, was unexpected. To those who know her, Zephirine Drouhin's high position is no more than she deserves; but what is one to say of Damascena N.L.849, which ought, from its classification, to be out of the running altogether, yet succeeded in beating every one of the HT's? No doubt it is a hybrid, but its performance is none the less meritorious. As for the poor sinners at the bottom of the list, I think Mevrouw van Rossem could have done better than she did, and ought really to have been excluded. Shot Silk shares with Rubaiyat the penalty for being too slow off the mark. It has done nothing since the 26th of September, but would have produced another fine burst of bloom if the summer had lasted another month; as it is, the last crop of buds has been sacrificed to the early frosts. Talisman was too lazy altogether; it rested for 31 days after its first flowering period, and for 37 days after the second; the buds for the third are barely showing now, four days after the closing date. Charles Mallerin is just where one would expect to find him; I suppose he possesses more serious faults than any other rose introduced in the past twenty years -- but so long as he can produce one of his perfect blooms in a year he will always have an honoured place in my garden.