Branching Out With Top Fruit Nutrition

In this episode we chat with Agrii fruit agronomists Matt Greep, Emma Smith and Ryan Williams.

We are focusing on top fruit and specifically the nutritional requirements of top fruit; why is it so important to get the balance right, what role does tissue analysis play in top fruit production and how can growers correct deficiencies?

Nutritional Requirements for Top Fruit Crops

What are Top Fruits?

Tony Smith:
Can you start by explaining what we mean when we refer to top fruits?

Ryan Williams:
Top fruits generally include apples and pears, but we’ll also touch on stone fruits like plums and cherries.

Tony Smith: 
And what is the main market for top fruits in the UK?

Ryan Williams: 
Most of the top fruits grown here are for conventional systems, supplying supermarkets. There’s also a significant amount grown for cider production, the wholesale market, juice, and even some varieties grown specifically for processing.

Nutritional Focus for Top Fruit Crops

Tony Smith:  
What makes the approach to nutrition different for top fruits compared to other crops?

Emma Smith:  
A healthy plant with its nutritional needs met is much more resilient to pests and diseases. With top fruits, you’re working with trees that may be in the ground for up to 30 years. You’re always thinking ahead—what you do this year will impact the crop next year.

Matt Greep:
Exactly, Emma. Because these crops are perennial, they hold onto nutrients for the following year. Extreme weather, like heavy winter rain, can wash away nutrients from the soil, meaning we need to assess each season and potentially make adjustments.

Ryan Williams:
If the correct nutrition isn't provided, the plant is more susceptible to pests and diseases, and in extreme cases, the tree could die. This is a massive expense for the grower, as it would need to be removed and replanted.

Key Nutritional Requirements for Top Fruit

Tony Smith:  
What are the key nutritional requirements for top fruit crops?

Matt Greep:  
The main macronutrients are nitrogen (N), phosphorus (P), potassium (K), and calcium (Ca). Calcium is particularly crucial for cell strength and division, especially in apples and pears. Other nutrients like magnesium, iron, and manganese are also important, particularly for stone fruits and vines.

Ryan Williams:  
I’d add that boron and zinc are critical during the flowering period. These help strengthen the pollen tubes, resulting in healthy flowers and ultimately better fruit.

Post-Harvest Nutrition and Reserves

Tony Smith  
You’ve mentioned the importance of post-harvest nutrition. Could you explain that in more detail?

Ryan Williams:  
Before the flowering period, the tree isn't drawing any nutrients from the soil but relies on its carbohydrate reserves. Ensuring that the tree has enough nutrients during the dormancy period is critical so that come spring, it has the strength to produce healthy flowers and fruit.

Similarities with Other High-Value Crops

Tony Smith:  
What similarities do you see between top fruits and other high-value crops like strawberries or raspberries?

Matt Greep:
In the UK, most strawberries are grown in inert substrates like coir, which have no nutritional value. We have to feed the crop with the right balance of nutrients at the right time to ensure healthy growth and fruiting. This applies to many other crops that are no longer grown in soil.

How Do Agronomists Assess Nutritional Requirements?

Tony Smith:  
How do you assess the nutritional requirements of these crops?

Ryan Williams:  
We use the Nutrient Management Guide (RB209) as a key reference. Section 7 covers fruit crops and vines, giving us guidelines on the age of the crop and the nutrients it needs. During crop walks, conducted every 10–14 days, we visually assess the plants and conduct tissue and soil analysis to ensure the crop is balanced.

Importance of Tissue Analysis

Tony Smith:  
How often do you conduct tissue analysis?

Ryan Williams:  
Twice per season is generally enough—once after blossoming and again around harvest. However, if visual assessments reveal any issues during the season, we may take additional samples.

Matt Greep:  
A healthy plant is a happy plant. Tissue analysis helps ensure that the crop has sufficient nutrients like calcium, potassium, nitrogen, and micronutrients, which are essential for avoiding storage disorders later on.

The Role of BioStimulants

Tony Smith:  
Can you explain the role of bio stimulants in top fruit crops?

Emma Smith:  
Bio stimulants are an entire subject on their own, with many types offering different benefits. They can stimulate the plant’s natural defences, improve nutrient uptake, and increase resilience to pests and diseases.

Ryan Williams:
For example, ProAct is a bio stimulant that can improve calcium uptake in top fruits, applied around blossom time and pre-harvest. It also helps plants become more resilient to frost, which is important with the increasingly unpredictable weather we’re seeing.

To wrap up, what’s your top tip for growers regarding nutrition in top fruit crops?

Matt Greep:
We’re seeing more extreme weather events—hotter summers, wetter winters. Bio stimulants can help crops cope with stress, allowing them to function normally and produce a good yield.

Ryan Williams:  
My tip would be: monitor, monitor, monitor. Regular assessments in the orchard, combined with tissue and soil analysis, are key to ensuring the crop is nutrient-balanced and post-harvest issues are avoided.

Emma Smith: 
For me, it’s critical to carry out these analyses. Without them, you won’t know if the plant is getting what it needs to maintain quality post-harvest, especially in crops like apples where shelf life can be several months.

To find out more about Agrii's fruit offering please visit our Specialist Fruit section