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Tobacco float-bed growers may want to check source water

If you haven’t already, now is the time to check the quality of your float-bed source water by sending it to a lab for analysis.

World Leaf News

According to the North Carolina Department of Agriculture & Consumer Sciences (NCDACS), being proactive early allows growers to take any necessary corrective action before filling beds and adding fertilizers. After fertilizer is mixed into float beds, it is also a good idea to submit samples to verify that nutrient concentrations are appropriate.

Solution analysis provides information important to uniform seedling growth, such as alkalinity, pH, electrical conductivity (soluble salts) and nutrient concentrations. The laboratory report also provides recommendations for corrective action, when necessary. “Following these recommendations can reduce production costs, disease pressure and other environmental and cultural problems,” said North Carolina Agricultural Commissioner Steve Troxler in a statement.

Nearly half of the source water samples taken from tobacco float-bed operations in North Carolina, and about one in five nutrient solution samples, have high alkalinity, sometimes known as total carbonates. Alkalinity values greater than or equal to 100 contribute to high pH and soluble-salt problems. The solution analysis report can provide recommendations for reducing alkalinity by 80 percent. If needed, alkalinity neutralization should be performed before trays are floated. The recommendations from the analysis should be followed carefully, as too much application of acid can lead to undesirably low pH and possible root damage.

To collect and submit a solution sample, North Carolina growers should follow these procedures:

1. Collect 8 ounces of solution in a clean plastic bottle. Small soda bottles are about the right size but should be triple rinsed with plain water (no soap). Remove or mark out any original product labeling. Make sure the sample represents the total solution. For example, for a source water sample, let the tap run for a few minutes before collecting it. For a nutrient solution sample, mix the fertilizer thoroughly and combine samples from several areas of the float bed to make one composite sample.

2. Complete the Solution Analysis Information sheet (form AD7). Select the appropriate solution code. “ST” is the code for float-bed source water. “NT” is for a nutrient solution, or one that contains fertilizer.

3. Send solution samples, a completed sample information sheet and the $5 fee per sample to the NCDACS Agronomic Division. For fastest results, be sure the package is addressed to the Plant/Waste/
Solution Section.