Pierre Notting (February 11, 1825 Bollendorf - November 2, 1895) started in the Zierpflanzengärtnerei Augustin Wilhelm (est. 1828) in 1845.
Soupert & Notting founded 1855 with Jean Soupert (February 2, 1834 - July 17, 1910)
Jean Soupert marries Pierre Notting's sister Anne Marie Notting in 1857.
Succeeded 1906 by Jean-Pierre Soupert-Hueber (1859 - October 5, 1916), Pierre-Alphonse Soupert (1862 - May 22, 1918) and Jean-Constant Soupert (d. 1942).
From 1917 onwards Constant Soupert & Cie.- see.
Jean Soupert & Pierre Notting [see also BREEDERS: Pierre Notting.] Luxembourg
Francine Cocard says that Soupert & Notting, just like Gemen-Bourg and the Ketten Bros., were breeders from Limpertsberg, a (then) suburb of Luxembourg-city.
[From The Old Rose Advisor, by Brent Dickerson, p. 145: This excerpt from the Journal des Roses] Born February 11, 1825, at Bollendorf, a hamlet near la Sare on the border of Luxembourg, Mons Notting passed his youth in very modest circumstance. From his most tender years, he evinced a passion for flowers... In 1845, he settled in Luxembourg, and labored as friend and worker at Mons Wilhelm's establishment, where he worked until 1855. It was then he got to know Mons Jean Soupert, ten years younger than himself, and the two of them founded the company so well known since that time.
[From Roll Call: The Old Rose Breeder, p. 483:]
Soupert [Jean] & Notting [Pierre]
NOTTING, Pierre (1821-1896)
SOUPERT, Jean (1831-1910)
[From Modern Roses 10, p. 733:] CONSTANT Soupert, Luxembourg; Jean-Gustave (GUSTAVE) Soupert; JEAN Soupert.
[From The Old Rose Advisor, by Brent Dickerson, p. 136, there is this entry from the Journal des Roses:] One of the greatest rosarians in the world... Jean Soupert, died last July 16th  at the age of 76. With him disappears one of the great figures of rosedom... Born February 19, 1834, in the environs of Luxembourg, Soupert, still quite young, began work at the horticultural establishment of Mons Wilhelm, a well-known firm there, where he was able to study all branches of horticulture... It was at Wilhelm's that he got to know his future brother-in-law, later his business associate, Mons Pierre Notting... It was in 1855 that the firm 'Soupert & Notting' was born... All his colleagues became his friends... The death of Notting hit Soupert hard, and... his robust health began to decline.
[Ibid, p. 151:] Alphonse Soupert, elder son of the great Luxembourgian rosarian
[From Medailles Attribuees aux Rosieristes Soupert & Notting, by Raymond Weiller:] Birth: February 20, 1834 (Luxembourg-Dommeldange). Death: July 17, 1910 (Luxembourg-Limpertsberg).
[From The Old Rose Adventurer, by Brent C. Dickerson, p. 131: Under the listing for 'Mme. Soupert'] Soupert was [in 1851] working for another nurseryman (one Wilhelm), and didn't open his own rose business (with Notting) until 1855.
[From Modern Roses V, p. 382:] SOUPERT & NOTTING, Luxembourg...(succeeded by C. Soupert).