Hydrangea flowers are some of the most stunning, dramatic blooms out there. Their huge globe-shaped flowers in bright blue, pink, white, or green put on an amazing show all summer long, and you can dry them and use them in arrangements to preserve their beauty in the colder seasons. But what if your prized hydrangea just won’t bloom? It’s more common than you might think, and there are a number of factors that can cause blooming to be stunted. Don’t worry, though, this guide will help you identify and fix the problem and, before you know it, your hydrangea will be bursting with vibrant flowers.
The soil hydrangeas are planted in has a huge effect on what their flowers do, so much so that you can control what color they turn by changing the acidity of the soil. If a hydrangea isn’t blooming at all, it may be because its soil is too rich in nitrogen. You can reduce the amount of nitrogen in your soil by mulching with sawdust or wood chips or planting nitrogen-loving plants like cabbage, squash, or corn nearby. An excess of nitrogen in the soil may also be due to the fertilizer being used on or near the hydrangea, which brings us to…
Too Much Fertilizer
Fertilizing hydrangeas too often makes them spend most of their energy on producing big, healthy leaves and not flowers. Either fertilize once in spring and once in mid-summer, or use a time-released fertilizer once in the spring only. More than that can stunt blooming.
Newly Planted Hydrangeas
Hydrangeas in their first or second year of being planted often will not give out blooms. This is because they are focusing the majority of their energy on growing a good root system to keep them strong and healthy in their new location. This is a good thing! Be patient with your hydrangeas and give them a year or two before you expect them to bloom.
Hydrangeas don’t require pruning, but in some cases it can promote blooming and give you a better display. However, incorrect pruning of hydrangeas is the most common cause of blooming problems because if you prune at the wrong time you can easily end up removing the early buds before they mature (more on correct pruning times here).
Hydrangea varieties fall into three different pruning categories: old growth (Hydrangea macrophylla), new growth (Hydrangea arborescens and Hydrangea paniculata), and Endless Summer series hydrangeas. Endless Summer and old growth hydrangeas should be pruned as soon as the flowers begin to fade. New growth plants should be pruned back in late winter or early spring. Find out which type of hydrangea you have and prune accordingly. If you are unsure of what type of hydrangea you have, skip pruning altogether and see if that helps it to bloom.
Sometimes hydrangeas are vulnerable to wind during the coldest months and need to be insulated over winter. You can protect them with a chicken-wire cage or stakes supporting a burlap wrap. Add fallen leaves or straw in between the plant and the wrap or cage for insulation.
The Wrong Location
If your hydrangea is getting too much shade, that may be why it isn’t blooming. Hydrangeas want partial shade, but they also need about 4 hours of dappled sun per day. Try transplanting to a sunnier spot if your hydrangea is in the dark all day.
Hydrangeas also need a lot of moisture, especially in the first one or two years. Plant them in soil that does not dry out completely, or else water daily in the summer.
Last, but not least, make sure you are picking hydrangea varieties that are appropriate for your zone. Just because one hydrangea does not work for you doesn’t mean that there isn’t another variety that will thrive in your climate.