Relationship between the German & Finish name
The relationship between the German/Dutch Gronow/Gronovius and the Finnish Gronovius/Gronows is based on family tradition of the Finnish Gronows. In mid 1800's a Finnish genealogist professor Wilhelm Lagus suggested that Christopher Johannisis Gronovius (and his brother Johannes Johannisis) was a son to the bailiff of the castle of Korsholm (western Finland) Hans Andersson. The theories on both German/Dutch origins and Finnish origins are based on secondary documents and the research continues.

Etymology 
Gronovius/Gronow is not a Finnish or Swedish name. A colleague of mine ambassador Jorma Inki made me a short etymology of the name Gronow. He localised several villages Eastern Germany and Poland with names Gronow, Grunow and Gronowe and assumed that the family originally comes from this area. In fact Gronows (both people and villages with this name) can be found in this area since 13th century.

Gronow, Grunow (or Grohno, Gruhno) are most probably geographical place-names transmitted by Sorbish. Its etymology disappears in the mutual borrowing of Slavic and German groups. It could have meant a vineyard, a bunch people or houses, a craggy ridge, a border village or an estate of a man with moustache.

Grono in Polish means a circle or bunch, for example "w gronie przyjacio´l" means in the circle of friends. In this context the original meaning word is bunch of grapes which is led to bunch, group and circle. In Polish the original form is grezno/grozno. In church Slavonic the word is grozd´. It has to be remarked that grapes exist only on the southern border of Polish, Sorbish and Wendish language area.

There is also word gran in Slavic languages meaning edge or needle (for example the Serbian word 'grana' meaning a branch and later even a limb). This word exist also in Polish and Sorbish.

Behind the word we can see the Indo-European "grgh" meaning a spike. For example perch (Perca fluviatilis) is still grgec is Croatian. The idea of 'gro/ grow' and the green colour (grön/grün) are also close. A shoot of a plant is sharp spike - compare with thorn and prickle.

The same word in ancient Icelandic is grõn meaning spruce, thorn and whisker. Meaning of spruce comes from needle. The form in Gothic is grano and in late Latin granus. The Lang bard name Ansegranus (late 9th century) probably meant a man with moustache (?). Lang bards lived long time close to Goths on Baltic sea. In some German dialects and in the Ablaut-stage even the form grune exists. In modern German "Granne" an awn of barley or rye.

Tito Gronow

Gronow, Gorzow PL Gronow, Zielona Gora PL Gronow, Zielona Gora PL Gronow, Sieradz PL Gronow, Jelenia Gora PL Gronau, Schleswig-Holstein DE Gronau, Nordrhein-Westfalen DE Gronau, Niedersachsen DE Gronau, Hessen DE Gronau, Hessen DE Gronau, Baden-Wurttemberg DE Gronau, Bayern DE