Calcium & Strawberry Quality – Why So Erratic

Calcium can improve firmness and quality but is poorly absorbed by maturing soft fruit. Most growers know that calcium is important for soft fruit, as it can improve cell wall strength which has a positive effect on shelf life, firmness and ability to withstand diseases. However when you look at the scientific evidence it becomes clear that the calcium applied to crops like strawberries does not always end up in the fruit. Calcium is poorly observed by maturing strawberry fruit therefore a lot of the calcium farmers apply to their crops is wasted as ripening fruit are not able to absorb it.

So why is it the case that calcium absorption is so erratic? Calcium absorption in strawberry fruit is strongly linked to the transport of auxin, a plant hormone. In strawberries auxins in the achene (the seed) are transported into the developing fruit, allowing the fruit to absorb calcium. However ripening is triggered by cessation of auxin transport into the fruit, so as the fruit starts to turn red the ability to absorb calcium rapidly declines.

Red strawberries have very little auxin, and can not absorb any calcium that is applied to them. So when crops are sprayed with foliar calcium, the leaves and green fruit will absorb it, but maturing fruits will not. Usually it is exactly the fruit that can not absorb the calcium that farmers are targeting, in order to improve firmness and post harvest shelf life. This is why results from conventional calcium fertilisers are so erratic, sometimes the fruit can’t absorb calcium into fruit and the input is wasted.

When you understand what causes problems with firmness (inability to absorb calcium) then you can develop smarter ways of supplying it.

I have been developing chemistry that helps calcium absorption for many years, the more we study the better we get at improving it. My research focusses on understanding the link between polar auxin transport, and calcium absorption.  By stimulating the pumps that are normally triggered by polar auxin transport, calcium can be absorbed by fruit in the absence of auxins. We use this science to make better calcium fertilisers at Levity and partner companies (Omex).


Albina, Levity’s new product for improving fruit firmness uses Levity’s pioneering chemistry, to stimulate calcium absorption into ripening fruit, where conventional products cannot. It can help soft fruit producers get firmness, fruit set, shelf-life to higher standards using very low inputs.

To develop fertilisers that work better we must first understand what farmers need, then look at the crop and understand what is causing the problem, finally we can then apply science to produce technology that provides solutions for farmers. When growers use Albina they will see good improvements over conventional products.

Albina Fertiliser Bottle

Please contact us for more information about purchasing Albina.

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Award winning scientist and experienced agronomist. With multiple patents, and proven track record of product development in biostimulants, pesticides and fertilisers.

Author: David Marks

Managing Director, Linkedin Profile