There are a lot of great flowering plants to add to your garden, including many staples, such as roses, zinnias, and hydrangeas.
However, depending on where you live and a few other factors, some plants may not be as viable as others.
Hydrangeas, for example, are easy to grow and produce incredible blooms, but that doesn’t mean they’re perfect for every garden setting.
A key factor in choosing whether or not to grow hydrangeas is often the bloom time.
When planning a garden with something in bloom throughout the growing season, these plants can become confusing.
Let’s look at when these plants bloom and what can encourage longer blooms.
How Long Do Hydrangeas Bloom?
One would think this is a simple question, but this is a genus of more than 75 species hailing from both Asia and the Americas, meaning they’ve adapted to a wider range of conditions.
This means that some hydrangeas will bloom earlier than others, and the average duration of their bloom times can also vary greatly.
Different Types, Different Blooming Periods
The first point we have to bring up is that five species of hydrangeas tend to be most popular in the US, each of which has a different bloom time.
- Bigleaf hydrangeas (Hydrangea macrophylla, which includes the mophead and lacecap variations) bloom from early July through August.
- Climbing hydrangea (Hydrangea anomala) blooms from late spring into summer.
- Oakleaf hydrangea (Hydrangea quercifolia) blooms from late spring through midsummer.
- Panicle hydrangea (Hydrangea paniculata) is a late bloomer, bearing its flowers from midsummer into September.
- Smooth hydrangea (Hydrangea arborescens) blooms from June through September.
Basic Duration vs. Potential Duration
Another thing to remember is that many factors can affect the bloom time.
For example, the disease can shorten or even prevent bloom time, and how you prune your hydrangea can have a huge effect since some species bloom on new growth while others bloom only on old growth.
This is one of the biggest reasons some people will have a long, healthy blooming period while others end up with short-lived or weak blooms.
Knowing when your particular hydrangea is supposed to bloom can help prevent panic if you expect early blooms on a late-blooming species.
Once it does bloom, you can keep the flowers coming for the maximum time by following a few easy care tricks.
How To Increase Bloom Time?
While it’s possible to let your hydrangea go through its bloom period without intervention, you won’t have as healthy or long-lasting blooms.
Here are some basic tricks to get the most out of your hydrangea bloom times.
Combatting Pests and Diseases
Hydrangeas aren’t particularly prone to disease, but a fungal infection such as leaf spot or powdery mildew can affect its ability to photosynthesize, affecting its ability to keep healthy blooms.
In most cases, these diseases will be caused because the plant cannot properly dry after rain or you’ve been using overhead watering techniques.
Proper lighting and giving your hydrangea enough space to air out are two easy ways to help reduce the risk of such infections.
Likewise, these plants aren’t exactly pest magnets, but they can draw aphids and spider mites when they’re not healthy.
These pests mainly attack the leaves but can also affect the flowers, especially if the infestation is allowed to grow.
Inspect your hydrangeas regularly for possible signs of infestation and treat them promptly or use neem soil soaks as a preventative.
Good lighting is essential for feeding a hydrangea in full bloom.
Full sun is generally best, but if you live in a particularly harsh southern environment, you can provide the full sun in the morning or evening with a little light or dappled shade at midday.
Flowering takes a lot of energy, and sunlight is one of the most natural ways to ensure your plant can feed those hungry blooms.
Pruning and Deadheading
This is where the real dilemma lies, as you will need to know whether your particular hydrangea uses hardwood or softwood to bloom.
When the species uses hardwood, you want to avoid pruning old growth.
This includes the bigleaf and oakleaf hydrangeas, which will have fewer blooms if you prune away the older branches.
In cases such as this, you will want only to remove dead or diseased growth, allowing for healthier growth to age.
But what about softwood blooming species?
When a hydrangea can bloom on softwood, it is often cut back severely before winter, usually down to 12” inches from the ground.
These species thrive on pruning, and the new, green branches will produce more blooms than if you allow them to age.
Deadheading is the practice of pinching or cutting off spent flowers to encourage new ones to form.
Because of how much energy is spent on feeding blooms, the process of removing spent ones allows your hydrangea to divert that energy to new nodes.
The result is a longer bloom period, sometimes resulting in a second wave of blooms.
We often talk about how to water your plants but fail to get into some effects you might not connect immediately.
For example, using an overhead watering technique can often result in water droplets getting on hidden or shaded leaves, which in turn can invite fungal infections.
Also, literally all but the tiniest percentage (3% percent or less) of water absorbed by the plant is used in a process called transpiration.
While not quite the same as when you sweat, there are many similarities, and one of the main roles transpiration plays is in regulating humidity.
This means the amount of water a given plant needs can change based on the temperature and other factors.
As a general rule, you’ll want to water your hydrangeas when the soil is dry 1″ to 2” inches down using a technique that provides water at or near ground level.
The best time for watering is in the morning, giving the ground time to absorb moisture before it gets too hot while also ensuring the temperature is warming up, so there’s faster absorption.
You can also add a little mulch to help ensure the soil doesn’t dry out too fast.
Remember, properly watering your hydrangea does more than give it a drink.
The process of transpiration will help prevent your hydrangea’s flowers from drying out and aid in several additional functions that can improve your blooms’ health, color, and longevity.