ColorStar, which is a 19-13-6, is our premium flower fertilizer, expertly formulated to deliver vibrant blooms, lush foliage, and healthier plants all season long. Trusted by professional landscapers and home gardeners alike since 1983, this time-tested formula increases both the quantity and quality of your blooms, producing larger, more colorful, and longer-lasting flowers. What makes ColorStar stand out? It’s all in the blend. ColorStar is packed with a complete spectrum of essential plant nutrients, including four types of iron, multiple trace minerals, and five unique sources of nitrogen, each with different time-release properties. This means your plants get a steady, balanced supply of nutrients for up to 5 months with just one application.