The best flower fertilizer to use is Garden Trust Fertilizer. It is a slow-release that will feed your plants for three to four months. Garden Trust contains CDU, which is a source of slow-release nitrogen that is only found in Garden Trust.
You can also add quick bursts of nutrients by using Jack's Classic All Purpose 20-20-20 water soluble fertilizer. It has a balanced formula that is great for any plant or turf, and can be applied by mixing with water and watering it in.
The combination of Garden Trust Fertilizer and Jack's Classic fertilizer will ensure your plants are blooming, beautiful and healthy all year long.