One of the most widely grown ornamental flowers in the world, gardeners are understandably obsessed with the hydrangea. The huge clusters that grow during the summer are enjoyed both indoors and out, so there’s something to look forward to every year.
Unless your hydrangea decides to stop flowering. Or it won’t start at all.
This problem, while worrying, is incredibly common. Take a look at these many reasons why your hydrangea may not be blooming and apply the solution to see your favorite blooms reappear.
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excessive sunshine
Hydrangeas grow and bloom best in partial shade conditions. While some species – hydrangea paniculata in particular, it can easily withstand a full day of direct sunlight, with some of the more common varieties needing shade for part of the day.
Excessive sunlight in species that are not used to it leads to heat stress. This dries out the soil, makes the foliage vulnerable to burns, and limits the plant’s ability to flower. Instead of growing more flowers, he focuses his attention on survival. Any flowers that appear may appear smaller and will not last long.
Be sure to plant your chosen hydrangea variety in the perfect spot to allow these beautiful blooms to appear. If you’ve already planted in the wrong spot, transplant to a more shady area or place a temporary shade cloth over the plants to give them some relief.
excessive shade
While hydrangeas need shade to thrive, too much can be a bad thing. These plants grow in wooded habitats where they are protected by overhead canopies and receive dappled sunlight throughout the day. If they get less than four hours of sunlight a day, they won’t have enough energy to thrive.
Avoid planting in areas with full shade. If you planted under a tree that has recently filled in, consider pruning it to allow more light for the hydrangeas below. You can also transplant to a sunnier location in fall or early spring.
A nutrient deficiency
Hydrangeas are generally considered heavy feeders and require a large amount of nutrients to thrive optimally. If you’ve planted in nutrient-poor soil or haven’t fertilized in years, you’ll eventually notice a lack of flowers, indicating a nutrient deficiency.
Always start planting in rich, fertile soil supplemented with plenty of organic matter. Then follow a consistent fertilizing routine year after year to maintain nutrients and give those plants everything they need to thrive effectively.
incorrect fertilization
Lack of flowers is not always a sign of lack of nutrients. It could also be a sign that your soil is getting the wrong amount of nutrients, either before planting or by using the wrong fertilizers.
High nitrogen and low phosphorus fertilizers can leave excess nitrogen in the soil. This causes your hydrangeas to develop more leaves and stems at the expense of flowers. If you noticed lots of new green shoots during the season, but no flowers, this is probably the cause.
To understand what’s going on underground, start by doing a soil test. Once you understand the existing nutrient ratios, you can choose a fertilizer to compensate for excesses or deficiencies to provide the ideal balance for re-blooming.
Here’s our guide to properly fertilizing hydrangeas so they bloom profusely year after year.
lack of humidity
Hydrangeas are moisture-loving plants that need constant water to thrive. If the soil is not kept moist, the plant will not have enough water for photosynthesis, providing the “food” it needs to put out the flowers. Underwater hydrangeas are stressed, in an effort to conserve water and focus on survival rather than flower production.
Water your hydrangeas regularly, especially in summer. Never let the soil dry out completely, but make sure it drains well enough to avoid waterlogging. Add compost before planting and mulch around the base to limit water loss through evaporation to retain moisture in the soil.
poor pruning technique
Pruning hydrangeas can be tricky work. This is because there are slightly different pruning techniques depending on the species you are dealing with.
Applying the wrong technique to a species is one of the most common causes of lack of flowers. Some hydrangeas, such as the popular H. macrophyllaThey only bloom on old wood. If you cut off these buds when pruning, there will be nothing left to grow into inflorescences the next season.
There is no way to fix this during this season, just wait until the next season for new buds to appear. To avoid this, follow our size guide to make sure you don’t cut any unexpected shoots.
pest problems
Hydrangeas are not the most susceptible plants to pest problems. However, they are not immune to these problems either. Several common garden pests, including scale insects, beetles, aphids, and especially slugs and snails, love hydrangeas and can establish themselves quickly. The damage caused by these insects weakens the plant and its ability to flower, resulting in a lack of flowers.
Treat any pest problems you notice immediately. Use follow-up treatments to make sure all infestations are completely gone. Make sure neighboring plants are also pest-free to prevent the problem from spreading to your hydrangeas.
disease problems
Diseases are also unlikely on hydrangeas, but not impossible. Powdery mildew is one of the most common problems, followed by rust and other fungal and bacterial diseases. Depending on the severity of the problem, they can cause leaf drop, draining the plant of energy needed for flowering.
Good garden hygiene is an important factor in preventing hydrangea disease. Give your plants enough space to let the air pass between the leaves and avoid overhead watering. Clean your tools before use and trim diseased areas as soon as you find them to prevent them from spreading.
Deer
If you live in an area where deer are common, you probably already know the damage they can cause. Deer are especially fond of hydrangeas, chewing the leaves and flower buds. Like improper pruning, hydrangeas blooming on old wood will need those buds the following season, severely limiting the number of flowers you’ll see that year.
The best defense is to keep deer completely out of your yard. Check out these many ways to keep deer away from your garden to protect your hydrangeas and other garden plants.
Incorrect temperatures or zone
Hydrangeas are fairly hardy plants, but they can’t stand extreme cold. For species that bloom on old wood, extreme cold in winter will kill the buds, preventing them from blooming the following season. If you planted in the wrong area or forgot to protect your plants from the cold, you’re unlikely to see many flowers the following year.
Start by choosing the right variety of hydrangeas for your area. Some are more cold tolerant while others can handle the heat. In winter, when frost is expected, protect plants with frost protection to limit damage so growth will be taller and stronger in the spring.
The hydrangea was a gift.
Gift hydrangeas that come in a small pot already in bloom are very different from those grown in a nursery. These plants are grown for the sole purpose of flowering quickly and profusely, using warm temperatures and plenty of fertilizer. If you transplant these potted hydrangeas into the garden, they are unlikely to grow well or produce new flowers quickly.
These plants are grown in greenhouse environments and are used at much higher temperatures than outdoors. Forcing plants to flower also makes them unsuitable for strong long-term growth, making flowering or even strong growth an uphill battle.
Potted gift hydrangeas are best kept indoors until they stop blooming, then discarded or used for their foliage as a houseplant. If you want to grow them outdoors, slowly acclimate them to outdoor conditions a few weeks before transplanting. However, don’t expect many flowers during this season, or even in the next few years.
Year
While many hydrangeas will bloom in the first year of planting, others will take a little longer to establish. Plants may need a year or even two to establish themselves before blooming profusely.
If you don’t see flowers the first year, all you need is a little patience. They should appear in a season or two.