Substrate moisture and fertilizer rate affect petunia growth
The cost of producing floriculture crops has increased due to increased cost of labor and fertilizer. Water scarcity and increasingly strict regulations regarding runoff pose additional challenges to greenhouse growers. Excessive irrigation causes most of the leaching and runoff of fertilizers and pesticides. In addition, the leaching of fertilizers is more prevalent when fertigation is used, but it can also occur with controlled release fertilizers. The resulting runoff poses a threat to ground and surface water quality, and many states regulate this runoff. Efficient irrigation methods reduce leaching and, thus, the amount of fertilizer needed to grow the plants. Reduced irrigation runoff also minimizes the environmental impact of greenhouse production and can reduce the cost of production.
Source: • American Floral Endowment Special Research Reports #531