Why Doesn't My Hydrangea Have Flowers?

Temperatures

Temperatures play a big role in flower production of the hydrangea. Most hydrangea varieties are cold intolerant, and temperatures below 25 degrees Fahrenheir will likely kill the plant. In northern zones with cooler temperatures, a few modern cultivars will thrive as far north as zone 4. These winter-hardy varieties include the endless summer and blushing bride. If a plant has previously done well and just won't flower, temperature may also be to blame. If a normally hydrangea-friendly zone experiences prolonged or especially cold temperatures, it is possible the buds have been killed.

Improper pruning may also result in flowering problems. If done at the wrong time of year -- early summer or late winter for most species -- flower production will most likely be stunted. The best time to prune a hydrangea is early spring, since the dead wood will be most obvious and over pruning is less likely. If over pruning occurs, particularly in summer, more sever dieback is likely during cold months. This damage may take a few months to be repaired, which may require waiting until the next year for flowers.

With hydrangeas, selecting a species that is suitable for the planting zone is crucial. If the temperature is too hot, too cold, or the soil isn't right, flower production may suffer. Finding a cultivar for the planting zone is fairly easy, and most types of hydrangeas will do well in a number of zones. Use the United States Department of Agriculture website to find which zone you are located in, and find a hydrangea species that fits. Some types of hydrangea produce flowers from old wood, stems that were established during the previous growing season, while others are limited to new wood. This means stems that grow during the current season, which may cause a delay in blooming.

There are approximately 16 elements required to keep a hydrangea healthy and blooming well. If even one of these is missing, it may negatively affect flower production. Hydrangeas should be planted in an area with nutrient-rich, slightly acidic soil. They require regular watering, particularly during the summer, but water should not be left standing for long periods of time. To assure healthy soil, add a bit of compost when planting and lay mulch around the base. Fertilization should be done in the spring in most areas and a second dose in August. In the South, the first fertilization should be done in May, and in northern areas, growers should wait until June.