“The bubbles become trapped and it creates these different textures and colours,” she said.
“People are increasingly looking for alternative photographic methods, going back to analogue roots.
“It appeals to my nature because each print is unique and individual.”
Mrs Welham laughed as she admitted she was “not an avid gardener” and said she hoped nobody wants to come and see her garden as a result of her win.
Asked how she might spend her winnings, she joked: “I certainly don’t need any photographic equipment.”
Tyrone McGlinchey, managing director of International Garden Photographer of the Year, said: “Jill’s image has proven that even old techniques are still capable of relevance, originality and immense beauty.
“Her knowledge and passion for the process has resulted in an extraordinary exposure of the Allium, adding complex textures and colour profiles analogous to the pioneering botanical cyanotype prints by English botanist and photographer Anna Atkins in the first half of the 19th century.
“The resulting exposure clearly draws from this rich and interesting heritage, but is unmistakably different in its approach and execution, making an image fit for the modern age in both its ability to communicate the beauty and importance of plant life as well as its capacity to represent the empowerment of women in art and science.”