The rarest of vegetable garden blooms

The kumara flower in Gillian Lovell's garden. Photo / supplied

She first saw one some 30 years ago, but the unexpected appearance of a purple kumara flower was still a special event for Kaitaia woman Gillian Lovell.

The flower didn't last long, she said, but was spectacular before it began to collapse.

Gillian's nephew, Kevin Matthews, said purple and gold kumara were very rarely seen flowering - the commercial yellow variety did so more regularly - but could produce blooms under stress, such as might be caused by a sudden change in weather. The variety in Gillian's garden had been in the Matthews family for well over a century.

"Māori, prior to the arrival of whalers and sealers, had some 80 named variety of kumara, a prized and valuable form of storable starch," Kevin said.

"They were cultivated and cropped over literally thousands and thousands of acres in Northland. The tonnage that was produced is mind boggling, even compared to today's commercial crops. The skill and degree of scientific plant knowledge needed to develop new cultivars is akin to modern day plant breeding research.

"The kumara were induced to flower by putting them under stress, by washing the soil away from their roots. The flowers were then cross-pollinated, and the resultant seed planted to produce a new variety. Cuttings from these varieties were planted out, and those deemed to be successful were kept. This could perhaps be termed as cloning of the parent seed stock."

Only four heritage cultivars - huti huti, taputini, rekamaroa (long sweet white) and houhere - remained today. Kevin's 92-year-old father (and Gillian's brother), Malcolm Matthews, was still growing taputini (bunch forming), along with tukau (large pink) and weina (purple with a purple heart), both of which arrived with whalers. He once had rekamaroa in his garden too, but it had been some time ago.

"He inherited these kumara from his father, Ronald Hayward Matthews, who got the plants from the Masters family on his return home from the first world war," Kevin added.

"Weina was named locally after its strong, vine-producing runners.

"And I am not the only one to believe that these older varieties are far superior to the modern day cultivars. The tubers may not be as 'pretty,' but they are certainly way tastier."