According to Buist (1838), a period of rest (or warm after-ripening?) can improve the germination and growth of Tea roses grown from seed.
[center]Magazine of Horticulture 4: 247-248 (July 1838)
Art. III. Experiments on the Vegetation of Rose Seeds.
By R. Buist, Florist, &c, Philadelphia.[/center]
Sir,â€”Some time last year I observed in your Magazine, a difference of opinion between two of your correspondents, in regard to the vegetating of rose seeds. I then determined on sowing some of the many varieties, and send you the result of my experiments.
No. 1. Seeds of Rosa indica odorata, or tea rose, were sown on the first of December, 1837, and vegetated in a temperature of between 58Â° and 65Â° Fahr., in from six weeks to three months, coming up occasionally during that period; the most of them have now bloomed, but not sufficiently strong to determine their character.
No. 2, of the same seed, and picked at the same time, was kept four weeks in sand, and sown on the ninth of January, 1838, and vegetated generally in seven weeks. The plants grew stronger and flowered better than No. 1, although treated in the same manner.
No. 3, seeds of the same, kept in sand till the first of February, and sown in pots and placed in dung or manure hot-bed, vegetated beautifully in six weeks, temperature from 65Â° to 75Â° Fahr., and are now promising, in growth, bloom and character, to surpass Nos. 1 and 2.
No. 4, seeds of Lamarque Noisette rose, collected from the plant in the open air in January, 1838, and sown along with those of No. 3, vegetated at the same time and have grown much stronger than any of the preceding, but only as yet three out of four plants have bloomed, and strange as it may appear, (you know the parent to be a large white,) one of those which flowered is a deep rose color and perfectly double. It perhaps may be desirable to say that the soil used was sand, loam, and leaf mould, in equal proportions, and watered with pure river water.