First, growers should send in samples of source water for solution analysis before planting. Solution samples, or water samples, are analyzed for general quality factors that may restrict proper plant growth. Solution analysis provides information on total alkalinity, pH, electrical conductivity and nitrogen, phosphorus, potassium, calcium, magnesium, sulfur, iron, manganese, zinc, copper, boron, chlorine and sodium levels. It is the only way to be certain that a water source or nutrient solution is suitable for tobacco seedling production. After agronomists review the chemical results, they make recommendations to help growers produce quality tobacco transplants.
Results are usually available within two to three days.
The second important thing for growers to remember is to wait two weeks after sowing before adding fertilizer to the float water. Since soil media usually contains fertilizer, an additional application is not needed during the first two to three weeks after seeding. The most common early problem seen by laboratory technicians is soluble salt injury to young seedlings usually due to the presence of too much fertilizer. Delaying the addition of fertilizer to the float bay until after germination minimizes the chance of this problem. And third, once the fertilizer is added, samples of the nutrient solution should be collected and analyzed for proper nutrient levels.