A timber based polymer coats the water soluble feed granule. This polymer has millions of tiny holes that allow water in which dissolve the feed. This then moves out of the granule at a controlled rate to feed plants for several months.

Sprinkle granules at recommended rates over the soil or compost surface and work lightly into the top 2 cm.

Yes, it will start feeding at that point for the remainder of the season

After they have emptied of feed the granules will gradually biodegrade over the next season or two. Being timber based the breakdown products will be recycled in the soil.

They can be used anywhere in the garden that allows incorporation into the soil.

Depending upon soil temperature they will feed for up to 6 months.

As long as there is some moisture in the soil/compost then the granules will start to release the plant food.

If left on the surface they will only release when soil moisture is high enough to allow water to enter the granule. This is likely to be intermittent and so is not recommended

For best results incorporate Phostrogen Slow Release Plant Food Granules into the compost when you are making up the container. This ensures even distribution among the roots and thus better feeding.

The granules should be mixed with the compost when planting up or repotting plants so this product can be used at any time of the year.

You can still add these to the soil by making little holes in soil and placing a spoonful in each hole or alternatively use the Phostrogen Slow Release Clusters which can easily be pushed into the soil to feed established plants for 6 months at a time.

The granules' outer coating hasn't had time to break down yet. The plant food dissolves and passes through the outer membrane via a process called osmosis. If it has been over six months since you added these to the soil then the chances are, there will be little or no feed value left and more should be added to the soil.