Hi, Vicki! There are more than 14,000 Osmocote reviews at Amazon, 81% are 5-star and another 13% are 4-star. Only 2% are 1 or 2-stars. The overall rating is 4.7-stars.

• Most all fertilizers are good for plants but research under controlled conditions shows a constant and continuous supply of nutrients over time outperforms an initial surge of nutrients - usually just nitrogen - followed by a long period of very little nutrient support, which describes how many organic fertilizers work.
• Osmocote achieves continuous release by adding a polymer coating to a nearly spherical prill of nutrients. The coating forms a shell around the nutrients. The shell you see is on the outside of the nutrient package. Its purpose is to control the rate of nutrients release. The coating, by the way, is a derivative of linseed oil, not petroleum.
• Nutrient release is triggered by soil temperature (not ambient temperature) and works with the natural process of osmosis. What that means is nutrients move through the coating (shell) into the soil at the same rate that the plant's root system pulls nutrition from the soil into the plant. Plants get what they need, but only when they need it!
• The control inherent in the osmotic process means there is no excess nitrogen to leach into streams, lakes or ground water, either. Another benefit of using Osmocote.
• Spent granules (depleted of nutrients) look like tiny beads. They are just empty shells and are not toxic. In fact, the shells while waiting to degrade help to aerate the soil, particularly if the soil is compacted (think, clay). Degradation of the shells takes longer than the time it takes for the nutrition to exit the granule. As time passes the shells will become very small before eventually disappearing altogether.

This is Bob Stohler pinch hitting for Marianne. He is the manager of the PlantersPlace.com website.