Preparation is everything when it comes to optimising cherry fruit-set with a plant growth regulator at flowering. It’s not always needed for all trees, nor in all locations. However, for certain varieties, like Staccato and Skeena, or when weather conditions are not ideal for pollination like last season, it can make a significant difference to yield.

As large-scale orchard developments continue to expand into non-traditional growing areas, particularly in Central Otago, being able to delay flower senescence for better pollination and fertilisation is a valuable crop management tool.

A simple and important step in your preparation is to order ReTain® early so you have it on hand for the short application window in spring, because accurate timing is essential.

Nufarm Technical Specialist Cynthia Christie explains: “Sometimes there is as little as 24 hours between ‘just right’ (30 percent flowering) and ‘too late’ (70 percent flowering), so if you don’t have ReTain ready to go, it’s easy to miss your opportunity.

Growers who use it successfully say they also keep a very close eye on development of their crops, so they know when the window is approaching.”

Efficacy is reduced from late applications, as most flowers are then past the stage where ReTain can make an impact.

ReTain is a naturally occurring plant growth regulator which reduces ethylene production in plant tissue. As soon as the cherry flower opens, the female part of the flower or ovule begins to senesce, and in some varieties, it is viable for a shorter time than others. ReTain effectively keeps the ovule alive for longer.

Delaying flower senescence also has significant benefits when variable weather over flowering affects bee activity. Bees are very sensitive to cold conditions and are not active if temperatures drop below 13°C.

For more information, contact your local Fruitfed Supplies Technical Horticultural Representative.

ACVM registration number: ReTain® Plant Growth Regulator #P004890. Read the registered label before use.