If you have some spare orchid fertilizer laying around it can be tempting to use it on other houseplants, but can you use orchid fertilizer on hoyas?
Orchid fertilizer can be used for hoyas, assuming it is complete and contains NPK in equal proportions. There are other fertilizers that are more suitable for hoyas specifically though, and they will have better results when used.
As an orchid and hoya owner I’ve had the experience of fertilizing both plants, so let’s take a look at why you can use orchid fertilizer for hoyas but also why you probably should use something else.
Why Orchid Fertilizer Can Be Used For Hoyas
Most people feed orchids with ‘complete’ fertilizers, which are those containing the three essential nutrients for growth. These are nitrogen, phosphorus and potassium – often abbreviated to NPK.
Orchids prefer balanced complete fertilizers, which means that the three nutrients are in equal proportions. This is typically displayed as 10-10-10 or 20-20-20 on the fertilizer label (meaning 20% nitrogen, 20% phosphorus and 20% potassium in the 20-20-20 case).
Complete fertilizers with equal proportions of NPK are suitable for most houseplants, including hoyas, as they are an excellent all-round option that includes all the necessary nutrients for plant growth. The three nutrients are specifically beneficial for different things:
- Nitrogen – Largely responsible for leaf growth due to playing a key role in coloring and chlorophyll production.
- Phosphorus – Beneficial for root growth and blooming/fruiting.
- Potassium – Great for all-round plant health and assists in the movement of water and nutrients.
Sometimes a different proportion of these three nutrients is better for certain plants, and I’ll get into this in more detail later specifically for hoyas. For now, let’s take a look at the types of orchid fertilizers to see which one is most suitable for hoyas.
Types Of Orchid Fertilizers
Here’s a quick rundown of what types of fertilizers are used for orchids.
Liquid fertilizers are mixed with water and then added directly to the soil just like during regular watering.
These can be applied very frequently and are suitable for those who own a lot of houseplants as they require a lot of dilution which leaves you with quite a large volume of fertilizer to use. I struggle to finish a small bottle of fertilizer during the summer even when feeding over 20 houseplants!
Spray fertilizers have gained a lot of popularity for orchids and are applied directly to the plant without the need for dilution.
The theory behind this type of fertilizer is that the leaves can absorb nutrients directly, but they are often found in very small concentrations and need to be applied quite frequently.
Slow-release fertilizers can last for up to half a year and release nutrients slowly into the soil.
They come in many forms, such as pellets and capsules, but can be quite tricky to use properly as you need a good understanding of how much fertilizer your plant really needs.
Granular fertilizers are similar to slow-release but work in a shorter time frame.
They are usually best applied when planting or repotting to allow them to mix properly into the soil.
Which Type To Use On Hoyas
Personally, I prefer to use liquid fertilizer for my hoyas.
I find that it is the best way to get the nutrients straight to the roots so the plant can absorb them right away. I have tried sprays before but they can oftentimes leave a residue on the leaves which I end up having to clean up.
Slow-release fertilizers are a good option, especially if you are going to be away from your plants for a longer period of time, but it can be tricky to know how much to use.
Is There A Better Option?
Orchid fertilizers can be used for hoyas without any issues, but they are not ideal. This may sound confusing, but let me explain.
Hoyas are mainly foliage plants – meaning they spend most of the time producing lots of small leaves. Nitrogen is especially important for this type of growth, so it makes more sense to have a higher concentration of nitrogen in the fertilizer.
During the summer months when the flowers start to bloom, phosphorus becomes more important to supplement this type of growth. So, you can simplify the type of fertilizer that you need for hoyas into two twpes:
- Higher nitrogen concentration for most of the year (aside from winter) to supplement leaf growth. 2-1-2 or 3-1-2 work well once or twice per month, depending on how quickly your hoya grow.
- Higher phosphorus concentration during the blooming season. 5-10-5 is great for this time of year once or twice per month at a diluted concentration.
Should You Fertilize Hoyas During The Winter?
I don’t fertilize my hoyas, or any plant for that matter, during the winter season.
Fertilizing during this time can cause a build-up of nutrients in the soil if the plant isn’t processing them quickly enough, which often is the case at this time of year. This can make leaching necessary, which is something I would rather not have to deal with.
If you live in a warmer climate where the winters are not very harsh you can definitely fertilize your hoya, but I would caution against using the fertilizers at full strength and would definitely dilute it quite a bit (either 1/2 or 1/4 strength).