Analyzing plant leaves is an indispensable method for effective nutrient management. Leaf analysis offers precise insights into a plant’s nutritional needs, aiding in the development of tailored nutrition programs. Timing is crucial, and conducting leaf analysis at the right moment allows us to rectify nutritional issues before they impact product quality and yield. Furthermore, considering the global rise in fertilizer prices, employing accurate leaf analysis can help minimize additional expenses by supplying only the necessary nutrients to plants.
Which Elements to Measure in Samples?
A significant portion of the analysis cost relates to the sampling process and transporting samples to the laboratory. Upon sending samples to the lab, we can request comprehensive analyses to determine the content of various elements in plant tissues. Primary macro and microelements must be included in the laboratory application form, encompassing nitrogen (N), phosphorus (P), potassium (K), calcium (Ca), magnesium (Mg), sulfur (S), boron (B), copper (Cu), iron (Fe), manganese (Mn), molybdenum (Mo), and zinc (Zn). Additionally, to obtain a comprehensive analysis, heavy metals such as lead (Pb), nickel (Ni), arsenic (As), cadmium (Cd), chromium (Cr), and mercury (Hg) can be incorporated in the application form.
Sample Collection Time
The ideal time for sampling fruit trees is during mid-summer, typically from late July to mid-August. During this period, most nutrient levels in the plant tissues remain relatively stable. However, if specific nutritional issues arise, sampling can be conducted at any time. In such cases, it’s advisable to sample both healthy and affected trees for comparative analysis.
Sampling Process
Sampling should be representative of the entire orchard, considering various factors such as cultivar, age, soil type, and nutritional history. The first step in accurate analysis is selecting the right leaves, which may vary depending on the plant type. Specific guidelines exist for most plants, but, in general, the following methods can be applied to fruit trees:
Sampling of Fruit Trees
- Ideally, sampling should be done a few days after the application of fertilizers or their use in the irrigation system.
- Young trees should be sampled every 2 to 3 years, while mature trees should be sampled every 4 to 5 years.
- Early morning is the preferred time for sampling, as temperature fluctuations throughout the day can affect nutrient levels in leaves.
- For first-time sampling in your orchard, it’s advisable to collect soil samples alongside leaf samples, allowing comprehensive nutrition program management using both soil and leaf analysis.
Sample Selection
For different fruit trees, non-productive branches without fruit and having a relatively vertical angle (45 to 60 degrees to the ground) are ideal for sampling. Nutrient concentrations differ between productive and non-productive branches. Choose branches from the outer parts of the trees and collect one or two leaves from the middle section of these branches. Generally, between 50 and 100 leaves should be collected from a maximum of 10 trees. Remember to label the sampled trees for future reference.
Selecting Suitable Leaves
Opt for leaves that have recently completed their growth. Very young or old leaves are unsuitable for sampling. Additionally, avoid damaged leaves affected by pests, diseases, or adverse weather conditions, as they may not provide accurate information about the plant’s nutritional status.
Packing and Transporting Samples to the Laboratory
After collecting the leaves, ensure they are free of dust and place them in paper envelopes. Write complete details on the envelope, including the sampler’s name, sampling date, location, the number of plants contributing to the sample, and specific tree details such as cultivar and age. Transfer the samples to the laboratory promptly or store them in a refrigerator until you can send them for analysis.