Will Geraniums Grow In Ericaceous Compost?

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If you want to grow geraniums, it’s important to make sure that you are giving them the right type of soil. So, will they be able to grow in ericaceous compost?

Geraniums might be able to grow in ericaceous compost. But they will usually struggle with the high acidity in the soil. Because of this, you might need to make a few changes before you plant the geraniums.

You need to match the soil requirements of your geranium to the type of compost you are using. This can mean making a few alterations to your ericaceous compost. Keep reading to learn how you get your flowers to grow strongly.

Table of Contents

Characteristics of Ericaceous Compost

Let’s start by looking at the ericaceous compost and what makes it so special. Here are some of the characteristics that make up this type of soil:

Acidic. This is one of the most defining elements of this compost variety. Typically, these mixtures will be between four to five on the pH scale. This is where the name comes from, as it appeals to ericaceous plants, which don’t perform well in soils that are high in lime. You can perform a pH test to find out exactly how acidic it is.

Variable NPK levels. It’s the pH that determines whether you have ericaceous compost. Because of this, the levels of other nutrients in the soil can vary, depending on the way the compost was created.

You should be able to find ericaceous compost at your local hardware store. If you purchase from here, the packet should tell you how acidic it is and the NPK. You can also make this type of compost at home. In this case, you will need to perform a few tests before you find out these levels.

Ideal Soil for Planting Geraniums

Now that we know the type of soil conditions ericaceous compost can create, we can compare that to the type of conditions geraniums require to see if they are a good fit.

The best place to start is by looking at the pH level the geraniums will require. They will usually like more neutral soil. The ideal conditions will have a pH of 6.5. However, they are fairly hardy, so they will be able to tolerate a range of soil conditions. But the most acidic soils they will tolerate have a pH level of 5.5.

Based on this, ericaceous compost won’t be a good fit for these plants. If the soil is too acidic geraniums will struggle. You might be able to mix in some ericaceous compost to reduce the pH to a more manageable level. But it will still place a lot of strain on the plant.

The next thing to consider is the NPK ratio, which tells you the number of nutrients in the soil. Before you plant, it’s best to increase the levels of potassium in the soil slightly. About a month before you begin planting, you should be using a 5-10-5 NPK ratio fertilizer. Once the plants are in place, it’s time to switch to a more balanced fertilizer, get something that has an NPK ratio of 10-10-10.

Here are some of the elements that you should be looking for when finding the right soil for planting geraniums:

Loamy soil. Usually, your geraniums will perform best in soil that offers good drainage.
Avoid fertilizers with too much nitrogen. This is a common mistake, which reduces the number of flowers you will be receiving. You will need to give them fertilizer twice a year, in the spring and the autumn.

While these conditions will be ideal for growing geraniums, they tend to be a fairly hardy species. They should be able to cope with being planted in poor soil conditions, as long as the pH is right.

Consequences of Using Ericaceous Compost for Geraniums

If you are applying ericaceous compost to the geraniums, you should monitor the plant. Their reaction to the compost will tell you whether they are going to thrive or if you are going to have problems. If you act quickly, you should be able to mitigate the worst of the problems.

Here are some of the signs that they aren’t responding well to the acidic compost:

Stunted growth
Brown dots appearing on the leaves
The outer edges of the leaves curve upwards

Yellowing of leaves, which is most common around the edges

The higher the acidity levels are the more significant these symptoms will become. While the geranium likely won’t die, they won’t be able to achieve their full potential.

Modifying Ericaceous Compost to Better Suit Geraniums

Before you plant the geraniums in ericaceous compost, it’s a good idea to modify it slightly. This will allow you to reduce the pH level of the soil to make it more manageable for the plants. There are a few ways that you can do this.

Combining With Multi-Purpose Potting Mix

The first option is to combine the ericaceous compost with a multi-purpose potting mix. This is best if you only want to use a small amount of ericaceous compost. Through mixing you will be able to unlock the nutrients of the ericaceous compost while reducing the pH level.

Adding Supplements to Raise the pH Levels

If you plan on using a large quantity of ericaceous compost, you will need to add some supplements. This will allow you to increase the pH levels, taking it back towards the neutral territory. There are a few ways that you can do this:

Adding lime. This is one of the most effective ways of increasing the soil pH level. How much lime you will need to use will depend on how acidic the compost is and the type of soil it is. For example, if it is a 5 on the pH scale and the soil is sandy, you should use around eight pounds of lime per 100-square meters.

Wood ash. This contains a similar chemical composition to lime. Though you will need to use more wood ash to see the same results as lime.
Eggshells. This is a third way of increasing the amount of calcium carbonate in the soil and boosting the pH level. It’s best to grind this up into a fine mixture, so it will be more easily absorbed into the soil.

After you have made these additions, you’ll need a few days for them to take effect. Then, test the soil again. You should be able to see some beneficial changes.

Checking pH

Before you plant your geraniums, it’s a good idea to check the pH level of the compost. This is very easy to do, you should be able to find a pH test in your local hardware store. All you need to do is take a small amount of the soil and dissolve it in water. Then, you can put it in the test strip. Wait a few minutes for it to dry.

The color the strip turns will determine the pH level in the soil. Remember, geraniums thrive around 6.5, but they can tolerate up to 5.5. Anything lower than this will need to be further modified before you start planting.

Final Thoughts

Getting the right type of soil is essential when you are planting geraniums. While they are tough to survive a wide array of conditions, they will still need to get the right pH levels in the soil. This is the biggest challenge when trying to plant them in ericaceous compost, as it tends to be too acidic. If you start to see problems occurring, you will need to make a few changes to the soil composition by adding amendments.

Sources

https://greenupside.com/4-ways-to-make-your-soil-more-alkaline-raise-soil-ph/#:~:text=To%20make%20garden%20soil%20more%20alkaline%2C%20add%20lime%20or%20dolomite,it%20can%20burn%20plant%20roots.

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