May - Spring Flowers on Postage Stamps

Aland 1997
http://en.wikipedia.org/wiki/Tussilago - Tussilago farfara (Coltsfoot) (top left)
http://www.luontoportti.com - Hepatica nobilis (Liverleaf) (top right)

Aland 1997

Australia 1959
http://en.wikipedia.org/wiki/Acacia_pycnantha - Golden Wattle

Canada 2005
http://www.almanac.com/plant/daffodils - Daffodils

Croatia 2012
http://en.wikipedia.org/wiki/Galanthus_nivalis - Galanthus nivalis (Snowdrop)

Denmark 2014
http://en.wikipedia.org/wiki/Fritillaria_meleagris - Fritillaria meleagris (Snake's head . . .)

Estonia 2003

Finland 1999
http://www.garden.org/plantguide/?q=show&id=2040 - Crocus

Finland 2000

France 1974 (Red Cross Stamp)

Great Britain 1953

Great Britain 2014 (Click to see all Spring Flowers)
http://www.luontoportti.com/suomi/en/kukkakasvit/common-dog-violet - Dog Violet
http://www.luontoportti.com/suomi/en/kukkakasvit/snowdrop - Snowdrop

Germany 1938

Germany 1969
http://en.wikipedia.org/wiki/Trollius_europaeus - Globe-flower (top right)
http://en.wikipedia.org/wiki/Adonis_vernalis - Pheasant's eye (top middle)
http://en.wikipedia.org/wiki/Lilium_martagon - Turk's cap lily (bottom left)

Iraq 1970

Iraq 1977 Spring Flower Festival

Iraq 1989
http://en.wikipedia.org/wiki/Pansy - Pansy

Ireland 1978
http://en.wikipedia.org/wiki/Gentiana_verna - Gentiana verna flower (top left)

Jersey 1974

Jersey 1974

Jersey 2009 (Click to see larger image.)
http://en.wikipedia.org/wiki/Primula - Primroses (bottom right)

Russia 1983 (Click to see larger image.)

Sweden 2003

Sweden 2005 (Click to see souvenir sheet.)
http://www.easytogrowbulbs.com//g-46-lily-of-the-valley-planting-guide.aspx - Lily of the Valley

Switzerland 1958 Postcard

Turkey 1955

Turkey 1955

Turkey 1960
http://en.wikipedia.org/wiki/Tulip (bottom right)

United States 2008 Postcard

Vietnam 1962 Spring and Summer Flowers