Hydrangeas are a gorgeous plant, adding bright pops of color and a sweet, fresh smell to summer days. Hydrangeas are hardy and relatively easy to grow, there are ways to make sure your hydrangeas are big, beautiful, and healthy.
When it comes to hydrangeas, what you use as fertilizer is just as important as when you apply the fertilizer. Plus, did you know you can change the color of some hydrangeas by altering the soil? Read on to learn more.
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The Basic Need of Hydrangeas
Generally, hydrangeas bloom in the spring, summer, and early fall. Each type of hydrangea is different, though, and many things affect when they bloom and for how long. In warmer climates, for example, hydrangeas usually bloom earlier and last longer than in cooler climates.
How a hydrangea blooms also depend on pruning. Some varieties of hydrangea bloom late or not at all if pruned in the spring. Pruning in late winter often leads to fewer, larger blooms the following spring and summer.
Other things that affect hydrangea blooms are over and underwatering, sun exposure, and fertilization. Hydrangeas are pretty easy to grow, but to make sure you get the brightest colors and healthiest plants; it helps to know the basic needs of this beautiful flower.
One of the key factors to growing hydrangeas is using the right type of soil. Hydrangeas are hardy, which means they can tolerate a lot, including a wide range of soil types. But which one is the best?
Loamy soil is a good choice. Loam is a mix of sand, silt, and clay, usually in a 40-40-20 ratio, respectively. The sand particles are the largest, and they ensure that the soil drains effectively and has good aeration.
The clay part of the loam is really compact. It’s not great for drainage or aeration, but it is much higher in nutrients than sand and silt.
So, it’s easy to see how sand and silt together are an ideal combination of hydrangeas. Sand ensures that the soil has good aeration and drainage and the clay provides the nutrient.
What does the silt do? It’s right in the middle. It holds moisture better than sand but doesn’t have as many nutrients as clay. It helps balance the two other ingredients, creating an ideal balance for garden soil.
If you’re planting hydrangeas in your yard, it’s important to know the makeup of the soil so you know what changes to make. For example, if your soil is rich in clay, add gypsum to break it up a bit.
If your soil is very sandy, add some peat moss. Peat moss not only helps hold onto moisture, but it’s also full of organic matter that will help encourage strong, healthy growth.
Location is really important for hydrangeas. They like a lot of sun in the morning and some shade in the afternoon, though this isn’t a hard and fast rule.
For example, if you live in a hot, sunny climate, your hydrangeas will only need about two hours of full sun in the morning and plenty of shade in the afternoon. If you live in a cooler climate, they can tolerate a little more.
As you can see, it takes some planning to find the perfect spot for a hydrangea bush. That said, if you need to move your hydrangeas to a new location, it’s not as difficult a task as you might think.
If you want to relocate your hydrangea bush, the best time to do so is in the autumn, after the plant has gone dormant. At this point in the year, the ground should not be firm and frozen yet, so it should be relatively easy to dig up the plant.
In warmer climates where the ground doesn’t freeze, you can move them any time after dormancy until late winter.
When the flowers have died and most of the leaves have fallen, it’s time to move. First, dig a hole in the location where you are moving the plant. Once the new location is ready, it’s time to dig up the plant.
Dig straight down into the ground around the root ball. Depending on the size of the plant, the roots may be big and heavy, so you may need help lifting it and moving it to the new location.
One you’re transported the plant to its new location, place it in the hole, and fill it in with soil. Thoroughly soak the soil around the plant and add some compost on top of the soil. Then, leave it be until spring.
When spring comes, water it regularly to make sure it establishes itself in its new home.
Water is an important factor when growing hydrangeas. They prefer moist soil that’s not too wet. You should never allow the soil to dry out completely, nor should you let it get too wet.
To facilitate this, you may need to make some adjustments to your watering schedule depending on the type of soil you have. Sandy soil will dry out quickly, but adding mulch can help keep moisture in. If you have clay-heavy soil, it holds on to moisture, so be sure not to overwater.
What Fertilizer to Use for Hydrangeas?
With hydrangeas (and most plants, really) it’s better to under-fertilize than over-fertilize. If you give your hydrangeas too much fertilizer, they will grow excess leaves and fewer blooms. This ratio puts the plant more at-risk for damage in the winter.
If your soil is rich enough or if you use something like organic compost on it, you may not need to fertilize your hydrangeas at all. In most cases, though, you will need to give them something.
The best option for hydrangeas is an all-purpose fertilizer with an NPK of 10-10-10. The continuous release is the best choice as this slowly releases nutrients into the soil, feeding your hydrangea shrub for months to come.
When is the Best Time to Fertilize Hydrangeas?
Timing is an important part of fertilizing hydrangeas, and when you do fertilize them is just as important as when you don’t.
When you should fertilize hydrangeas depends on where you live. In warmer climates, you may want to fertilize twice a year, once in late spring and again in midsummer. In cooler climates, one application in midsummer is usually enough.
It’s important not to fertilize your hydrangeas too late in the season. Never fertilize hydrangeas after August. Hydrangeas go dormant over the winter and naturally begin slowing down in the fall.
Fertilizing in late summer can stimulate new growth, but this growth will not be strong enough to survive the long, cold winter.
If your soil is depleted and you want to replenish it in time for the growing season, you can apply a slow-release fertilizer in late winter or early spring instead of waiting for late spring.
How to Fertilize Hydrangeas?
How you fertilize your hydrangeas depends on your soil. Ideally, you should test your soil before adding fertilizer. It’s always better to under fertilize than over-fertilize, and you really don’t know what your hydrangeas need unless you test the soil first.
There are many types of fertilizer for hydrangeas, but we recommend using a slow-release granular formula. By using this type, you ensure that your hydrangeas get a slow and steady amount of nutrients over a long period of time.
To apply, follow the instructions on the container of the fertilizer you choose to get the correct rate. After applying, you can blend the granules into the top two to three inches of soil. Some fertilizers recommend watering the fertilizer in; others do not. Follow the manufacturer’s instructions for the best results.
There are plenty of organic options for fertilizing hydrangeas, too. Some of the things you can use are:
- Tea from grass clippings. To make this fertilizer, take some grass clippings and let them steep in a large bucket of water for a few days. Then strain the clippings out and apply the water to your hydrangeas. This method is a great way to add nitrogen to the soil, which your hydrangeas need to green leaves.
- Aquarium water. If you have a freshwater aquarium, when you do water changes, save the water and use it on your hydrangeas about once a month. Again, this adds nitrogen, but it also contains fish detritus, which is full of nutrients. (Note that this applies only to freshwater tanks, not saltwater).
- Animal manure. It’s not surprising that animal manure is a good fertilizer, but you may not have known it’s a good choice for hydrangeas.
- Household compost. If you have a composter, mix some of the compost into the soil around your hydrangeas.
- Vinegar. Vinegar is a good source of phosphorus, magnesium, and potassium. Add a teaspoon to a quart of water and apply it to the roots. This method also increases the acidity of the soil, which hydrangeas love. You can also change the color of the blossoms from pink to blue by increasing the acidity of the soil.
How Often to Fertilize Hydrangeas?
As mentioned, how often you will fertilize your hydrangeas depends on the climate where you live. In a warmer climate, fertilizing twice a year is ideal. Do this once in the spring and again in midsummer.
In a cooler climate, you often only need to fertilize your hydrangeas once a year, in midsummer.
That said, it’s important to remember that the best way to figure out how and when to fertilize anything, including your hydrangeas, is to analyze your soil. Soil testing is the only way to really know what you need to add to the soil to make sure your hydrangeas grow strong and beautiful.
As you can see, a lot goes into caring for a hydrangea, though, overall, it’s an easy plant to take care of. If your plant is in the right location and you water and fertilize it as you should, your hydrangeas should return year after year, keeping summer looking and smelling a bit sweeter.