Scotts 18-6-12 Osmocote (50 lbs) High Sidewall Water vapor penetrates the shell

Water vapor penetrates the shell and dissolves the nutrient core into the surrounding soil/media

See below for the exact description

The thread on the unit itself is proprietary

Temperature and Wear: Best to apply in the morning above 50 degrees F (10 degrees C)

Scotts 18-6-12 Osmocote (50 lbs) High Sidewall Water vapor penetrates the shellDescription Specs FAQs Osmocote Plus and Osmocote Classic products are 100% coated and designed for use in greenhouses with herbaceous crops. Controlled release fertilizer applications to landscapes can provide a season long feeding with a single application and help reduce nutrient runoff as well. Scotts 18 6 12 Osmocote Label [PDF] How long does Osmocote Fertilizer really last? Osmocote labels contain information on the expected fertilizer