More information on Schmidt-Michel, mainly from German sources:

Conrad Peter Strassheim, editor of the publication Rosen-zeitung : zeitschrift des Vereins deutscher rosenfreunde, "discovered" and promoted Lina Schmidt-Michel. From 1890-1911, almost all of the pictures in Strassheim’s rose newspaper (about 200 total) were painted by her.

Schmidt-Michel produced illustrations for other publications as well. E. C. Nelson writes that she “…was one of the principal artists who worked for Journal des roses, a French periodical published in monthly parts between 1877 and 1914. Its prime purpose was to promote cultivars produced in French nurseries; each part had a colour lithograph portraying a new rose. To quote Brent Dickerson, Schmidt-Michel's work ‘captures not only the beauty of the roses, but also the spirit of their time’—I agree: they are blowsy, opulent, redolent of that age.”

Anny Jacob, author of the book “Rosen-Porträts” which features many of Schmidt-Michel’s illustrations, states: "She painted almost all rose pictures of the Rosen-Zeitung from 1890 to 1911.”

In 1903, Schmidt-Michel designed a greeting card for the opening of the Rosarium Sangerhausen (now Europa-Rosarium) in Sangerhausen, Saxony-Anhalt, Germany. The card featured the plan of the Rosarium and the rose named for the German Empress, “Kaiserin Auguste Viktoria,“ (Hybrid Tea, bred by Peter Lambert, Germany, 1891).

"Despite much research," Jacob writes, "we know nothing about the life of Lina Schmidt-Michel.” “Also, only one original illustration of the artist’s is known. It is a pastel of the Hybrid Perpetual “Regierungsrat Stockert," bred by Soupert & Notting (Luxembourg, 1888). The hundred-year image is still fresh and beautiful.
In 1906, Peter Lambert introduced the rose “Lina Schmidt-Michel.” At the time Jacob published her book, the rose was still blooming in Rosarium Sangerhausen (As of this writing, it’s listed in the Europa-Rosarium online database). Jacob’s book was the first “comprehensive appreciation of a painter who incomparably understood how to combine the documentation of the botanical essence with high aesthetic appeal."