These two new additions of the double Profusions — Hot Cherry and Deep Salmon — have been named 2013 All-America Selections winners. Their double blooms stand out in large containers and baskets. Flowers cover the plants from spring through frost with minimal care.
Peat-lite mixes work well at a soil pH of 5.5 to 6.2. Optimum EC level is 1.0 to 1.2. Cool temperatures can invite disease and foliage problems (below 60° F). Warm temperatures can stretch the plants (above 75° F).
Weekly applications of 200- to 250-ppm nitrogen using a well-balanced calcium nitrate-based fertilizer help to produce high-quality plants. Zinnia is sensitive to boron deficiency, characterized by tip abortion, crinkled leaves and leaf edge burn. Applying 0.25 ppm of boron with each fertilizer application is highly recommended.
Zinna Profusion Double has good disease resistance and is not generally attacked by the many foliar diseases that affect zinnia. Good sanitation and growing culture will also aid in keeping the plants healthy. Do not place heavy mulch around the base of the plants as this may cause stem rot at the soil line.