Jobe's 10 Pack 9-12-9 NPK ratio Rose Spikes. These slow release spikes are made with bone meal and feather meal, providing your roses with the nutrients they need to grow healthy and produce beautiful blooms. Simply insert them into the ground around your rose bushes and water as usual. The spikes will release nutrients into the soil over time, unlike surface fertilizers that can wash away with rain or watering. Give your rose bushes the extra nourishment they crave with Jobe's Fertilizer Spikes for Roses.