Gardeners have been told what blooms to grow this season for the longest-lasting cut flower, and zinnia tops the bill.

Zinnia flowers lasted longest in tests

Seed firm Johnsons of Suffolk carried out a trial of 11 flower species that are popular for cutting.

As well as seeing which blooms stood the test of time, the company tried to see if vase life could be extended.

Zinnia came top, with flowers lasting 24 days with a two-day water change. Flower heads were “still as good as the day they were picked” 17 days into the trial, claimed Johnsons.

Echinacea, also subjected to a two-day water change, came second, with flowers lasting 22 days. Aster was a runner-up.

Johnsons’ Leila Russell said: “We’ve heard so much about growing vegetables in the last two or three years and there is now an increasing trend for customers to grow their own flowers, which is just as rewarding.

“They are very economical when compared to shop-bought flowers, especially when we consider how long they can last,” Leila explained.

Echinacea was a runner-up

Researchers tried to find out if treatments could extend vase life. These included adding a penny and an asprin to vase water, adding lemon juice, sugar and bleach, and using cut flower food – all with water that remained unchanged.

However, the most successful way to extend vase life was changing the water every two days. This, said Johnsons, kept vases free of the bacteria which triggers flower decay.

Leila summed up: “A simple change of water every two days seems to beat all the so-called tricks of the trade.”