What type of fertilizer should I use on my hydrangea?

I recommend a fertilizer that is higher in phosphorous than nitrogen. Phosphorous, P in the NPK ratio, helps hydrangeas grow flowers. A fertilizer that is high in nitrogen will grow leaves at the expense of flowers. To learn more about nutrients and their impact on flowers, including flower colors, take a look my hydrangea soil science video. Remember, it’s also important to know when to fertilize. I give the answer to that question in the video too.