When planting shrubs in the ground, you can add potting mix to the existing dirt. However, I prefer to work in compost or additional topsoil. Your Diamond Rouge Hydrangea will flower better with some additional fertilizer. Be careful that you don’t overdo it. You don’t want to burn the roots. A balanced fertilizer with similar NPK numbers is best to get it started. Next year, look for a fertilizer with a higher middle number in the ratio to help grow flowers. Before you prune your hydrangea, be certain to watch my video!
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