Can You Use Ericaceous Compost On Hydrangeas?

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Hydrangeas are some of the most unique and beautiful shrubs you can add to your yard or garden landscape. Like all plants, these beautiful shrubs need good food to stay beautiful and healthy. Can you use ericaceous compost? Is it too strong? Should you use it at all?

Gardeners can easily grow hydrangeas in ericaceous compost. In addition to giving hydrangeas nutrients, ericaceous compost will change the color of the blooms from pink to blue or even purple. Hydrangeas can also be grown in neutral and alkaline soil.

If you want to learn how ericaceous compost works for hydrangeas or the alternative composts you can use for hydrangeas, you need to keep reading the info we’ve got below!

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Can Hydrangeas be Planted with Ericaceous Compost?

Yes, you can absolutely plant your hydrangeas with ericaceous compost. Hydrangeas are very tolerant of soil pH, so you can plant them in either acidic, neutral, or alkaline soils, and they will grow perfectly fine.

However, acidic soil is what hydrangeas like the best, so ericaceous compost mixes are highly encouraged among gardeners who grow hydrangeas.

Normal compost is a little acidic, but it’s mostly neutral. If you have basic compost, you can add organic matter like the following to make it more acidic:

Coffee grounds
Oak leaves

Fresh pine needles

If you need an example of ericaceous compost, a mixture of perlite, sterilized soil, compost, sand, and peat moss will work very well! When it comes to what hydrangeas love in their soil, some nuances with the minerals will help you determine what fertilizers you should use for this shrub.

But we’ll get to that in a later section. First, how does ericaceous compost actually help hydrangeas with their acid?

What is Ericaceous Compost for?

If you’re reading this right now, you definitely already have some idea of what ericaceous compost is. At the very least, you know it’s acidic now. Ericaceous compost typically lies between 4.0 and 5.0 on the 0-14 pH scale, where 7.0 is neutral and anything less than it is acidic.

The acidic pH at this scale helps many plants, such as,

Azaleas

Berries
Cedar
Mushrooms

And yes, hydrangeas.

For plants like these, acid is necessary to help them break down the nutrients in the soil to be adequately absorbed and prevent excess absorption of aluminum, iron, and magnesium by dissolving and reducing them. Why is that important? Do these minerals hurt plants like hydrangeas?

Having enough iron will keep the leaves from yellowing by allowing your shrub to produce lots of chlorophyll, but the acid can help break down the iron into a form that the roots can more easily absorb.

Gardeners commonly use aluminum sulfate to artificially increase the soil’s acidity, but too much aluminum can burn the hydrangea’s roots.

Lastly, magnesium keeps chlorophyll healthy, but without a magnesium deficiency in your soil, it shouldn’t be added as magnesium sulfate because it can prevent the plant from absorbing other minerals.

What pH Levels do Hydrangeas Like?

As we touched on earlier, hydrangeas are very forgiving when it comes to soil pH, though acidic soil can make it easier for the shrub to absorb nutrients if necessary.

Instead of making sure the soil is at a particular pH for the health of the shrub, changing the pH in either direction is the magical element that changes the color of the blooms.

There are different colors for different pHs:

Alkaline

Neutral
Slightly acidic
Very acidic

The higher the pH is, means the more alkaline and aluminum deficient your soil is; it will turn into a lighter and lighter pink, while blooms at a neutral pH can be moderate or dark pink.

If your soil is slightly acidic, with some aluminum, the blooms will be a deep blue, and then higher acidity and greater aluminum produce lighter and lighter blue blooms.

So ultimately, pH depends on your personal preference. So if you want pink, should you ignore ericaceous compost? Not entirely.

What are the Benefits of Using Ericaceous Compost for Hydrangeas?

For hydrangeas to grow, survive, and thrive, they require two key nutrients: nitrogen and phosphorus. The nitrogen will allow the hydrangea to produce chlorophyll, a necessary component for converting sunlight into energy.

The phosphorus will allow the hydrangea to convert existing nutrients in the soil into the building blocks that make it grow tall and full of flowers.

Ericaceous compost is beneficial for hydrangeas for several reasons:

It’s rich in nitrogen
It’s rich in potassium
It prevents phosphorus from being lost

For most plants, if the soil is too acidic, too alkaline, or just simply not at the necessary pH the plant wants, certain nutrients will be “unavailable,” even though they’re in the soil. Hydrangeas, like begonias, don’t have this problem because they are versatile.

The ericaceous compost is often made with ingredients such as coffee grounds and wood ash high in nitrogen and potassium. It doesn’t typically come with phosphorous, which creates more blooms than usual, but it will protect any added phosphorous from being washed away.

So even if you prefer the pink blooms but notice your hydrangea is deficient in any of these nutrients, some ericaceous compost or balanced N-P-K fertilizers would help. Does this mean your shrub will die if you don’t use ericaceous compost?

We should note that If you have hydrangea varieties such as the Panicle or Oakleaf varieties, they will maintain their white color, so your choice in compost will just depend on what nutrients your variety needs at the time.

Do Other Compost Mixes Work for Hydrangeas?

Don’t panic! It’s not rigidly necessary to use ericaceous compost to keep your shrub healthy; it just has some significant benefits you should be aware of. There are a number of other compost choices, such as:

Green compost (nitrogen-rich)

Brown compost (carbon-rich)
Bark compost
Multi-purpose

Any nutrient-rich compost will be perfect to use, and if any of you like to grow an abundance of different kinds of plants, you probably have plenty of multi-purpose compost lying around.

If there is a second-best compost for hydrangeas after ericaceous, it would be the multi-purpose type because its pH and included nutrient-rich organic matter is carefully compiled to feed and maintain a wide variety of flora.

You can usually be sure that multi-purpose or all-purpose compost will have everything your hydrangea needs, regardless of the variety you have.

The weakest option may be bark compost, which has the least nutrition and works more like mulch.

Check out: Coffee Grounds For Hydrangeas

Is Homemade Ericaceous Compost Just as Good as Store Bought?

So long as your homemade ericaceous compost has the organic matter that decomposes into the minerals your hydrangea needs and passes a pH test with the level you want, it will be just as good as a bag from the garden center.

Common ingredients to use for your ericaceous compost include, in addition to the pine needles and coffee grounds are:

Peat moss
Oak leaves

Beech leaves

Conclusion

So, you see? Not only is ericaceous compost a great way to change the color of your hydrangea blossoms, but it’s also a terrific way to keep these gorgeous additions to your garden, well, gorgeous!

And so long as they have their sun/shade, nutrient, and water needs met, they really are some of the easiest shrubs to keep alive.

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