6 Simple Steps For Keeping Your Hydrangeas Blue

Are you struggling to keep your hydrangeas blue this season? It actually all comes down to the type of hydrangea you own, and soil science. In this article, gardening expert and hydrangea expert Jill Drago provides six simple steps for keeping those beautiful blue blooms!

Hydrangea Kept Blue During Blooming Season

When I close my eyes and daydream about a beautifully blooming hydrangea, the image that comes to my mind is ‘endless sky blue‘ with big balls of flowers peeking through a white fence. This is the goal for many gardeners, regardless of experience level.

Growing hydrangeas is easy enough once they are established in your garden. They require a good amount of water, but with the right placement, you will otherwise be in for some low-maintenance beauties all summer long.

If you are trying to keep your hydrangeas blue this season, there’s a few simple steps to follow. You’ll need to make sure you have the correct species, pay attention to soil acidity, and much more. Let’s take a deeper look at six simple steps you’ll need to follow in order to keep your blooms bright blue this season!

Step 1: Start With The Right Species

Blue Flowering Plant
Hydrangea macrophylla and serrata are the plants that produce blue blooms.

If blue flowers of are what you are seeking for your garden this season, then you’ll want to make sure that you are starting with the correct species. Not all hydrangea types will produce blue blooms, so if you pick the wrong one, you are already fighting a losing battle.

There are six popular species that are used in home gardens, each of them has their own special beauty. However, the only two species that create blue flowers are Hydrangea macrophylla (bigleaf) and Hydrangea serrata (mountain).

Keep in mind that there are many different blue varieties that fall under these species. Some have bigger blooms, and some are smaller. Some of them are more compact, or dwarf varieties, whereas others are full size.

Bigleaf and mountain hydrangeas will come in white, pink, purple and blue and most of them will be sensitive to the pH of the soil which is how you end up with blue flowers.

A Few True Blue Hydrangeas:

Step 2: Plant in The Right Location

Shrub blooming in the garden
These prolific bloomers grow best in partial shade and well-drained soil.

Hydrangeas do best in fertile soil that is well draining. This allows them to stay nice and hydrated and able to produce those beautiful blooms you are hoping for.

There are a few areas in your landscape that could give you some difficulties. You will want to avoid planting them near any concrete structures. Concrete can leach silica and calcium oxide into the soil and could cause the soil to become alkaline. Alkaline soil will not hurt them but it will make it very difficult for your flowers to stay blue.

Bigleaf, as well as mountain hydrangea, thrive in partial shade. This means about four to six hours of sunlight, preferably morning sun. Any more sun than that could lead to the drying out of your plants. They also love soil that is fertile and well-draining. This provides enough moisture to the plant without running the risk of root rot.

Step 3: Test Your Soil

gardener making a soil test
A soil test will give you information about nutrients, soil pH, and N-P-K levels.

Once you have picked the perfect spot, it is recommended that you perform a soil test. Soil tests are easy to do and are available at your garden center, or online. The soil test will give you a lot of information about the soil. This could include information on the nutrient density, and most importantly when it comes to blue flowers: the soil of your pH.

Soil pH is measured in a range from 0-14. A rating of 7 is a neutral soil. Any ratings below 7 are signs of an acidic soil, while ratings above a 7 are considered to be sweet or alkaline. The best soil pH for blue flowers is right around 5.5. It’s important to keep this balance if you notice the blooms are beginning to change color.

Also, take note of the N-P-K levels you receive from your soil test, this information can help you determine if you need any extra fertilizer at all. The soil may be perfectly fertile on its own, and adding anything may throw off the soil’s balance and affect the health of your plants.

Step 4: Acidify Your Soil

gardener holding compost
You can acidify the soil in your garden by adding compost or soil acidifier.

Once you have determined the acidity and alkalinity of the soil, you’ll be ready to get started. Of course, if your soil is already acidic you do not need to do anything! Lucky you, your soil is already perfect for blue hydrangeas!

If your soil is alkaline you will probably want to work on acidifying it. There are a few ways to do this. If you are a more patient gardener, adding compost over time will slowly increase the acidity levels.

Of course this will mean you will need to wait longer for your blue flowers. Adding compost also has so many benefits. Adding organic material that is rich in nutrients will fertilize your plant as well as improve your soil.

Soil acidifiers are available at your garden center. These products will help you achieve those blue blooms more quickly. These acidifiers are granular and you should follow the application instructions on the bag.

Step 5: Keep Them Watered

gardener watering shrubs
You’ll want to ensure you water regularly, especially for freshly planted shrubs.

This might seem obvious, however keeping them well watered will help them in many ways. When it comes to flowers, they can become dehydrated just like the rest of the plant. Once flowers dehydrate, they will begin to wilt, crisp up and inevitably turn brown.

In addition to getting crispy, you run the risk of fertilizer burn. For fertilizer to work correctly it is best for the roots to be nice and hydrated before application. If you fertilize a dry plant you may notice some dried out edges on your leaves as well as your flowers.

Plants that are fully established in your garden will not need to be watered quite as much as new plantings. New plantings may need to be watered every day, especially through the warm season. Whereas established plants may only need to be watered twice a week.

When watering, always remember to water the base of the plant to avoid any possible fungal diseases that could negatively impact the leaves or the flowers.

Step 6: Consider a Container

Blue flowering plant in container
If you plant in a container, it will more easily allow you to control the pH level of the soil.

Another great option for beautiful blue hydrangeas is to grow them in a container. It is much easier to control the soil pH in a container than in the ground.

When you are planting them in a container you will want to follow the same steps as you would if you were planting one in the ground, you just probably won’t need a soil test. Use a potting soil specifically for acid loving plants if you can find it. If not, using your soil acidifier works great- just follow the labeled directions!

When they are grown in containers it is a good idea to keep in mind that these plants will need more frequent watering than those in the ground. The root systems will only have so much available water to drink and will dry out much quicker.

This means you may need to water everyday. Just keep your eye on the plant to avoid any drying out and all the negative side effects that come along with that!

Final Thoughts

Blue hydrangea blooms are achievable no matter your gardening level. The most important things to keep in mind are the species, growing location, soil makeup, and giving them the maintenance that they need. If you follow these steps you will be in for bountiful and beautiful blue blooms!

dwarf hydrangea


17 Dwarf Hydrangea Varieties You Can Plant This Season

Thinking about adding some dwarf hydrangea plants to your garden this season, but aren't quite sure which type to plant? Finding the right hydrangea tht's a bit small and more compact, can really make a difference depending on the size of your planting space. In this article, gardening expert and hydrangea enthusiast Jill Drago examines her favorite types of dwarf hydrangea.

Deadheading Hydrangeas


11 Tips For Deadheading Hydrangeas Correctly

If you are trying to deadhead your hydrangeas for better blooms this season, you aren't alone! Deadheading is the art of removing spent blooms so that new ones can come and take their place. In this article, gardening expert and hydrangea enthusiast Jill Drago walks through her top tips for properly deadheading this season.

prune hydrangeas


How to Prune Hydrangeas in 7 Simple Steps

Pruning your hyhdrangeas is more of an art than science. These beautiful flowering shrubs are quite common all over the United States, and the world. In this article, gardening expert and hydrangea enthusiast Jill Drago takes you through each step of properly pruning your hydrangeas.

Perennial Hydrangeas Outdoors


Hydrangeas: Are They Annuals, Perennials or Biennials?

Thinking of planting some hydrangeas this year, but want to know if they will return the following season, or if you'll need to replant them? The answer will depend on your hardiness zone. In this article, gardening expert Jill Drago examines if hydrangeas are annuals, perennials, or biennials.

pink hydrangea


16 Pink Hydrangea Varieties With Beautiful Bright Colors

If you are thinking of adding some pink hydrangeas to your garden this year, you might be confused on which varieties will look the best. There are a number of different varieties you can choose that will flower with beautiful pink blooms! In this article, gardening expert and hydrangea enthusiast Jill Drago lists out the most popular pink hydrangea varieties you can grow this season!

Lacecap Hydrangea in Blue


How to Plant, Grow, and Care For Lacecap Hydrangeas

Lacecap hydrangeas are a wonderful addition to any garden. But if you've never grown them before, where do you start? Lacecaps can be a bit pickier than other types of hydrangea, so it's important to understand all their needs before you begin planting. In this article, gardening expert and hydrangea enthusiast Jill Drago highlights every step you'll need to follow when growing lacecap hydrangeas this season.