Ask the Expert: What fertilizer is used for non-flowering Hydrangea
What fertilizer is used for non-flowering Hydrangea? Jen

Reply:
The primary nutrient for bloom production is phosphorous. You can apply super phosphate 0-18-0 or triple phosphate 0-45-0 a few months prior to blooming. However, lack of nutrients may not be the reason your hydrangeas are not blooming.

There are three main causes that can contribute to lack of hydrangea blooms.

1. Too Much Shade. If hydrangeas do not get enough sunlight, they will not produce blooms. The foliage will be healthy and beautiful but the blooms won't appear. Although they like a little shade from intense heat, they will need at least half a day sun to produce blooms.

2. Improper Pruning. In the winter, you can remove about a third of the old stems to create a fuller and healthier plant in all hydrangea types. However, the proper time for height control and deadheading will differ based on the type of hydrangea and how it blooms. Big leaf and Oakleaf hydrangeas bloom on last year's growth. In this instance, the hydrangea must be pruned shortly after they have finished blooming - usually within a month. Pruning anytime after that will essential destroy the next year's blooms. Panicle and smooth hydrangeas bloom on new growth and should be pruned in the spring before they put on their new leaves.

3. Unfavorable Weather. If at anytime the hydrangeas break dormancy and then the temperatures drop, the blooms will be damaged. This usually occurs in place where the weather see-saws from cold to warm and then to cold again.

To ensure that your hydrangea blooms next year try the following:
1. Prune it correctly.
2. Make sure it gets enough light.
3. Fertilize it with triple phosphate, super phosphate or a balanced fertilizer that is high in phosphorous like Fertilome's Azalea, Camellia, Rhododendron Food 9-15-13.