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Is Wood Ash Good For Hostas?

People are always looking to use something useful in their gardens. This is fully justified because everything should be done with maximum efficiency.

Wood ash can be good for hostas as long as the soil in which they grow is very acidic. The wood ash is able to greatly increase the pH, so it should only be used if the pH is below 5.5.

We will explore this question in more detail below. In this article, you will learn how to determine whether or not to use wood ash and how to apply it correctly.

wood ash on hostas

What does wood ash do for hostas?

Wood ash contains many minerals that are good for hostas. If you have poor soil, wood ash can add value to it.

First, wood ash contains a lot of potassium. This element is one of the three basic elements that are needed for plant growth.

Second, this product contains calcium, which is responsible for the strength of the stems and foliage. In addition, wood ash contains iron and magnesium, which are necessary for photosynthesis.

However, wood ash is a very alkaline product. This is good if you have very acidic soil. Putting some of it in very acidic soils will slightly increase the pH and that can have a positive effect.

In case your soil is neutral or slightly alkaline, adding wood ash will make it even more alkaline. But hostas do not like alkaline soil, so in this particular case, using wood ash is harmful.

How to apply wood ash for hostas?

To determine if you can apply wood ash to the soil, you need to know the pH of your soil. To do this, buy a soil pH test kit from a garden supply store or online. Use it as directed on the label.

If the pH of your soil is below 5.5, your hostas can benefit from using wood ash. But if your soil pH is above 5.5, avoid applying this product as it may harm the hosta.

Let’s say your soil is very acidic and some wood ash can be applied. You can only use wood ashes from raw wood such as those from a fireplace. Avoid using ashes from treated wood, such as construction timbers, etc.

Shred large chunks of ash before spreading. It is best if you shred everything into a powder, this will have a quicker effect.

Spread the crushed ash around the hosta. Use no more than a tablespoon of ash for each hosta.

Next, take a hand spatula and mix the ash with the soil. Be extremely careful not to damage the roots of the hosta.

When to apply wood ash?

The best time to apply wood ash to hostas is early in the season. Sprinkle the ash around March and once is enough for the whole year or more.

Early in the season is good because the hosta will get the minerals at the start and will use them to grow well. A later application will be less effective.

The second appropriate period is planting or transplanting the hosta. If the soil in which you plant it is too acidic, the wood ash will balance it out.

Simply pour some ash into the planting hole and mix it with the native soil. Also, add some organic matter to make the soil lighter and more nutritious.

Is wood ash safe for hostas?

Wood ash is safe for hostas if applied correctly. It is not aggressive and you do not have to fear that it will burn the leaves or stems of the plant.

Moreover, wood ash is used to disinfect plant wounds. So this product has also antiseptic properties.

However, wood ash can have a negative effect on the hosta if it is obtained from unsuitable wood. This includes treated or painted wood, plywood, and other building materials. As a result, such ashes can contain harmful toxins that can harm not only the hostas but also you.

Also, using wood ash in neutral or alkaline soil can cause negative effects. This will make the soil even more alkaline and the hostas may feel a lack of nitrogen and other elements. This can lead to the yellowing of the leaves and stunted growth.

What if you’ve already applied wood ash to your hosta?

Suppose you have applied wood ash, but then you realized that your ground is neutral. To avoid negative consequences you need to act immediately.

The first thing to do is to remove all the wood ash you have spread. Just rake everything around the hosta and throw it in the trash.

If you have mixed the ashes with the soil, you need to remove the top layer of the soil. Carefully remove 1 inch of soil around the hosta without damaging the roots. Replace this soil with fresh soil.

The second way is to transplant the hosta. Dig up the bush so as to save as many roots as possible. Move the hosta to a new location where the soil is slightly acidic or neutral and plant it there. Add some organic matter to the planting hole.

Alternatives to wood ash

There are several alternatives to wood ash, depending on what you want to achieve. Let’s take a look at some of them.

If your soil is too acidic and you need to balance it out, the best alternative is garden lime. It is a natural product made from natural materials. You can buy it at almost any hardware store.

In case you need to fertilize your hostas, the alternatives to wood ash are organic matter and mineral fertilizer.

Organic fertilizer is one of the best types of fertilizer for your hosta. It is usually compost which is very nutritious and safe for hostas. In addition, compost can improve the structure and quality of the soil.

The best mineral fertilizer is slow-release pellets. Their advantage is that they last the whole season and contain all the substances that hostas need. In addition, this fertilizer does not increase the alkalinity of the soil, unlike wood ash, which in the case of hostas is crucial.