Pre-flower Is A Good Time For Leaf Analysis

When it comes to maximising crop yields, commercial growers face a never-ending battle to refine their cultivation processes and account for whatever circumstances nature throws their way. 

A grower’s fertilisation regime obviously has a profound impact and growers need accurate data to understand what regime best suits their crop needs. Leaf analysis is a major source of this data and can help growers develop an appropriate fertilisation program. To get the most out of a leaf analysis, growers should take samples at the right time to create a picture of their crop’s health.

Why do a leaf analysis?


Leaf analysis is a critical diagnostic tool that helps growers understand the nutritional status of their crops and identify any nutrient deficiencies that need to be rectified before they become a more serious issue. 

With this knowledge, growers can make informed decisions about whether changes need to be made to their fertilisation regime to better meet the needs of their crops. This can potentially save growers a significant amount of money that would otherwise be lost to crops producing lower yields, and inferior size or quality or miss spent on the wrong fertiliser.

When to take a leaf analysis?


Creating a routine schedule of leaf analysis provides growers with a good set of reference data that can be used to catch any deviations in nutrient levels over subsequent seasons. When samples should be taken is determined by the plant’s physiological stages (first true leaves, pre-bloom etc) not by the calendar. With regular analyses, growers can develop a more sophisticated fertilisation program with more precise fertilisation rates and timings to maximise their yields. 

In order to get the most accurate result, growers should take care to choose the correct leaves as samples. Generally, nutrient levels are best gauged through the most recently matured leaf. This is because nutrient levels are at their most stable at this time, as opposed to less mature leaves that tend to exhibit a greater fluctuation in nutrient levels, or older leaves, as some minerals move from older leaves to younger leaves.

Analysing samples prior to flowering can be especially useful. Doing the analysis toward the beginning of the crop cycle, at the pre-flowering stage, affords growers a chance to catch deficiencies with adequate time, so steps can still be taken to correct imbalances before the most crucial phenological period – flowering.

For example, if a crop has a manganese deficiency this will impact numerous processes such as photosynthesis as the leaves exhibit a yellowing chlorosis affecting respiration, and nitrogen assimilation. Manganese also plays an important role in the resistance of pathogens such as Powdery Mildew on cucumbers or grapes. However, with accurate information the crop can be turned around quickly with a rebalanced application of highly available manganese fertiliser. 

Keeping on top of crop health is absolutely paramount for any grower. Taking the time to conduct leaf analyses at appropriate times, particularly in the pre-flowering stage, provides a large measure of protection against reduced yields, diminished quality and plant health. 

If you are a commercial grower, contact Molly at rsf@rd2.co.nz to book a free nutrition consult.