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Everyone wants to make sure that their houseplant is thriving. To do this, you will need to create the right soil conditions. But is multi-purpose compost the right choice for houseplants?
Multi-purpose compost will be suitable for most houseplants. But succulents, cacti, and acid-loving plants will need specialized compost. Except for any special plants, sharp sand can be added for better drainage.
Multi-purpose compost allows you to infuse nutrients into the soil for healthy growth. Keep reading to learn more about what soil conditions houseplants need and how to customize the compost mix to better suit them.
Properties of Multi-Purpose Compost
There are a few properties of multi-purpose compost which make it a good choice for houseplants. First, it has a lot of organic matter. This will break down within the soil, providing the nutrients that the houseplants need to grow.
Furthermore, it has been designed to have a neutral pH level. This will benefit most plants, allowing them to easily absorb nutrients from the soil. Generally, houseplants will thrive in soils that have a pH of between six to seven. If you aren’t sure what the pH is, your local hardware store should have a test kit. As we’ll discuss later, there are some ways to amend the soil to get the target pH.
Multi-purpose compost will often contain materials like gravel, sand, or bark. These are designed to increase the drainage within the soil. This gives the roots the space they need to breathe. Plus, it helps protect against root rot by allowing the water to drain.
Finally, multi-purpose compost will often have a wetting agent. This helps retain moisture within the soil. Traditionally, this was peat. However, today there are synthetic alternatives that serve the same purpose.
Choosing the Right Multi-Purpose Compost
The clear majority of plants will benefit from the use of multi-purpose compost. But not all types of multi-purpose compost are created equal. Here are some tips you can use to find the right one for you:
- Consider the NPK Levels. This is one of the most important elements when choosing any compost. NPK stands for the amount of Nitrogen, Phosphorus, and Potassium. These are the most important nutrients which affect plant growth. The ideal NPK for houseplants is 3-1-2.
- Whether you want peat. Lately, more manufacturers have been removing peat from their compost mixes. This is primarily done to protect the environment. An alternative wetting agent will need to be used instead.
- Size of the bag. If you are planning on using it for houseplants, you likely don’t need a huge bag. While compost doesn’t go off, it will lose its nutrients over time.
The good news is that you don’t need to shell out the big bucks for a premium compost mix. Usually, your houseplants won’t be overly fussy. As long as you choose a multi-purpose compost from a reputable company, they will respond positively.
What Types of Plants Aren’t Suitable for Multi-Purpose Compost?
A few types of plants won’t be suitable to grow in multi-purpose compost. These include:
- Succulents. These will require a high level of moisture within the soil. It’s best to pick a loamy mix.
- Cacti. Because these plants require dry soil, there is a risk that multi-purpose compost will cause root rot.
- Acid Loving Plants. Finally, the neutral pH levels of multi-purpose will make it hard for acid-loving plants to absorb nutrients from the soil. As we’ll discuss later, there are some ways to increase soil acidity. But it’s best to plant with ericaceous compost.
How to Apply Multi-Purpose Compost to Plants?
Once you have found the right type of compost, it’s time to start using it on your houseplants. There are a few tips you should keep in mind to get the best results:
- Water after applying compost. This helps the nutrients flow through to the plants to be adequately absorbed.
- Spread it generously. Apply the compost generously over your plants. It can be around 40mm deep.
- Add some fertilizer. Just because you are using compost doesn’t mean that you can neglect to fertilize your plants. There are a few ways you can do this. You can add some slow-release granules. These will last for a few months. Or you can use a liquid solution. This can provide a targeted burst of nutrients as the plants start to flower.
- Replace compost yearly. Compost won’t last forever. After a year, the nutrients will have been absorbed into the roots, so you’ll need to top up the compost.
Modifying Multi-Purpose Compost
The reason why multi-purpose compost is so popular is that it will benefit most types of plants. Generally, you will be able to use it straight out of the bag.
But that doesn’t mean that all houseplants will thrive in multi-purpose compost. It’s recommended that you do a little research into the specific conditions that your species requires.
There are three areas that you will need to consider. The first is the amount of drainage it will require. You can check if this is a problem by sticking your finger a few inches into the soil. If it is damp, it means that the plants don’t have enough drainage. This is particularly common amongst peat-free compost. There are a few ways you can add drainage to the compost; these include:
- Adding some additional gravel or sand
- Using some perlite
- Putting some rocks at the bottom of the pot
- Drilling additional holes in the pot
The next thing to consider is the pH of the soil. Multi-purpose soil is pH neutral or slightly acidic. If your plants prefer a more acidic environment, you might want to use ericaceous compost. Though there are a few ways you can make a multi-purpose compost more acidic:
- Mixing in some ericaceous compost
- Adding sulfur
- Using organic matter, like leaf litter.
Finally, you might want to make the soil a little more alkaline. The best option is to sprinkle in a bit of lime.
It should be noted that pH isn’t static. Every six months or so, you’ll need to re-test and adjust the pH level if necessary.
Other Types of Compost
While multi-purpose compost will suit most houseplants, it isn’t the only option available. Here are some of the other options you can explore.
As the name suggests, this is best used when planting seedlings. Because of this, there is a greater focus on drainage. Plus, it will have a fine texture. There are plenty of nutrients within the soil. But these will be released slowly, supporting the growth of the root system.
However, this isn’t a long-term solution. Once the strong root system has been established, you’ll need to move your houseplants to a larger container. This is when you will need to start using multi-purpose compost.
As you might have guessed, this compost has more drainage than multi-purpose compost. This serves a few important functions. First, it increases the water retention of the soil. It also makes for thicker compost. This is the best approach for top-heavy plants and requires a more robust root system.
As we mentioned earlier, this is better for houseplants that require strongly acidic soil to grow. You’ll know that your plant will need this type of compost if the edges of the leaves turn yellow. This can signify that it can’t absorb nutrients properly due to the high pH level. At other times, the wrong soil pH can cause leaves to shrivel up, and the plant can die.
Check out: Ericaceous Compost for Houseplants
Getting the right soil conditions is the key to solid plant growth. For most houseplants, multi-purpose compost is the ideal choice. It has the proper nutrients to support a healthy root system and help plants flourish. It has a neutral pH level, so the plants can easily absorb the nutrients.