Slow release fertilizers (SRFs) are products that are able to supply plants with nutrients for a period of several weeks. Unlike controlled release fertilizers (CRFs), slow release fertilizers do not use a coating technology to slow down the release of nutrients. They are based on minerals containing nutrients in longer molecules that need more time to break down. Unlike CRFs (that are only influenced by temperature), the release of nutrients from SRFs are influenced by temperature, water, soil pH and microbe activity.
In ornamental horticulture, slow release fertilizers are used to get a fast greening effect lasting for a few weeks. Also, SRFs may be used as starter fertilizers when balanced nutrition is needed for a couple of weeks. ICL offers slow release fertilizers for ornamental growers under the brand Osmoform®.
Benefits of slow release fertilizers
- Extended nutrient availability up to a few weeks
- Improved plant growth
- Reduced fertilizer applications
- Reduced risk of nutrient runoff and leaching
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Calculators to improve nutrient management and boost productivity
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With N, Ca, and Mg for new substrates
The shift to new growing media is a fact, no more a trend. Peat-free and peat-reduced substrates require specific fertilizer solutions. New growing media such those containing woodfiber, bark or coir, have lower buffering capacity for both water and nutrients, require higher N fixation and are more susceptible to pH fluctuations. For this reason it is important to adjust the supply of nutrients and irrigation through the growing season. In many countries PSM (potting soil manufacturer) deliver growing media ready-to-use because they have adjusted the nutritional inputs. In some regions though, growers create their own mix. In both cases the most important thing is to know how new substrates interact with nutrient elements. Cal-BOOST has been specifically developed in case of nitrogen draw down and/or extra calcium or magnesium is needed.
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Bringing vibrant color to your nursery stock.
The leading slow-release granulated fertilizer that gives you dazzling color.
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