Time to collect leaf samples for nutrient analysis
Editor’s note: This article is from the archives of the MSU Crop Advisory Team Alerts. Check the label of any pesticide referenced to ensure your use is included.
Leaf analysis is the best way to monitor the nutrition of fruit plantings. This procedure provides a direct measure of the nutritional health of plants as soil tests only provide an estimate. Leaf analyses can be used to diagnose nutritional problems and to identify developing problems before growth or yield is affected. Sample young plantings every one to two years and established plantings every two to four years. The whole farm can be sampled every three to five years, or portions sampled more frequently.
- Define sampling units. Divide the farm into sampling units or areas that have uniform soil types, management history and variety. Farms with variable soils or history will require more sampling units to provide an accurate picture of the nutritional health. If the farm is very uniform with large blocks of the same age and varieties, define units no larger than 10 to 15 acres.
- Sampling. Sample leaves in late July to early August. Collect at least 50 leaves from different plants throughout the sampling unit. Select healthy leaves from the middle of this year’s shoots. If the leaves are dusty, rinse them briefly in tap water, and lay them out on a table top until they are dry to the touch.
- Submitting samples. Package leaves in clearly labeled paper bags, and send them to a reputable laboratory.
- Diagnosing nutritional problems. If you wish to diagnose a suspected nutritional problem, collect one sample from plants beginning to develop symptoms of the problem, and a second from nearby healthy plants. These samples can be collected at anytime during the season.