Does Rubber Plant Need Fertilizer? (What Kind, How Much & More)

Rubber plant aka Ficus Elastica, is a popular house plant as they are sturdy and easy to care for. You don’t need to do much for this plant to thrive. But providing them with appropriate plant food is essential. Does rubber plants need fertilizers? If yes, what type and how much? Let’s find out!

Rubber plants need a high phosphorus fertilizer at their early growth stage as it facilitates healthy root growth. As the rubber plant mature, you must use an NPK fertilizer of 24:8:16 ratio to stimulate rapid and bushier growth. Fertilize the plant every 4-6 weeks, and avoid over-fertilization as it will make the plant leggy.

You need to be cautious while fertilizing your rubber plant. Both under fertilization and over-fertilization could be an issue.

Also, it is crucial to note the time of year when you are fertilizing them.

I know that is a lot of information for you to take in. So, let’s dive into some details and take each of those doubts one at a time.

Should I fertilize my rubber plant?

Yes, you must fertilize your rubber plant for a fuller and healthier growth. Rubber plant grows really big (up to 8 feet) even in indoor conditions if provided with the right lighting, pot, and other requirements.

These plants can absorb the required nutrients from the soil during their initial stage.

However, as they mature and the soil’s nutrients deplete, you need to add some fertilizer to revitalize the soil.

If you do not provide the plant with appropriate nutrients, then their growth rate might get affected.

You might have learned that plant uses sunlight for the process of photosynthesis. It is the process that converts water, Co2, and sunlight into food.

However, the soil nutrients are still crucial as it acts as vitamins for the plants, and without it, they cannot grow healthy.

It’s similar to malnutrition in humans; if you do not provide an adequate diet, the body’s growth will be affected, and the same is true with plants as well.

Your rubber plant may struggle to grow if enough food is not provided to them. Here are some signs of an under fertilized rubber plant:

• Stunted growth
• Leaves losing its color
• Edges of the leaves turning yellow/brown
• Younger leaves turning yellow and drooping
• Weaker root growth
• Leggy plant growth

If you notice any of these symptoms, your rubber plants are probably not getting enough food to grow and thrive.

Also read: Why is my rubber plant not growing?

What kind of fertilizer is good for a rubber plant?

I can understand it can be challenging for you to pick the right fertilizer for your rubber plant. But don’t worry, I am here to make things simple for you.

In each package of fertilizer, you will notice something like N:P:K ratio something like 10:10:10 or 20:20:20. These number denotes the composition of fertilizer where the first one is Nitrogen followed by phosphorus and potassium.

Now you need to understand that each houseplant has different needs of fertilizer.

The fertilizer need also depends upon the location of your plant which means indoor plants will have different needs than outdoor plants.

You even need to understand that each of these nutrients has a different role in developing the plants.

Nutrients	Role
Nitrogen	-Essential for photosynthesis -Helps stimulate growth of leaves and foliage
Phosphorus	-Encourages root growth -Essential for flowering and fruiting plant
Potassium	-Helps regulate water intake -Helps fight off diseases -Makes plants resilient

Rubber plants can grow pretty big, and to continue their growth, they need an appropriate mix of fertilizers.

You must use a fertilizer of 24:8:16, where the mixture contains the right balance of Nitrogen, Phosphorus, and Potassium.

The need for nitrogen is much more than other nutrients because rubber plant leaves are pretty big and they need the same to produce larger-sized leaves.

Types of fertilizers

There are basically three types of fertilizers you can use on any houseplants. These include:

1. Liquid fertilizer
2. Granular fertilizer
3. Slow-release fertilizers

Liquid fertilizers are the most commonly used fertilizer for most of our house plants.

It is available in two forms i.e., a concentrated liquid or powder form. In either case, we need to mix it with water and dilute the same before using it on our rubber plants.

Liquid fertilizers are the most preferred form of synthetic fertilizer as we can control the exact dosage, reducing the risk of overfertilization, especially for beginners.

Granular fertilizers are mostly available in the form of pellets. This type of fertilizer can be mixed with the soil and fed to your plants.

We do not recommend using granular fertilizer on rubber plants as they release all the nutrients in one go, which increases the risk of overfertilization. Thus, it is not recommended at all.

Slow-release fertilizers are also available as pellets, but they are coated with a shell that slows down the release of nutrients, and as a result, the nutrients release slowly into the soil whenever we water the plant.

These are better than granular fertilizer, but the problem is we cannot dilute to meet our rubber plant needs, which decreases the flexibility.

Thus, the best synthetic fertilizer available for rubber plant would be a liquid fertilizer.

Compost as fertilizer for rubber plant

Compost or worm casting is another excellent way to fertilize your rubber plant.

Compost is basically made up of natural waste and organic materials, which decomposes over time, allowing us to use the same on our plants.

This natural fertilizer acts as a replica of nature in the forest where the barks, leaves, branches all decompose, and the soil absorbs the nutrients.

The same principle works here without house plants. We can add a handful of compost and water our rubber plant.

The nutrients present in the organic matter will slowly sip into the soil, making it rich in nutrients.

However, there are two significant concerns two this:

1. Compost or worm casting can sometimes produce foul smell which might not be pleasing for everyone.
2. The ratio of nutrients cannot be controlled.

Although compost is a well-balanced mix that provides our plants with essential nutrients.

However, they do not contain these nutrients in an appropriate ratio. Thus, it might not be sufficient for all plants. However, you can definitely use it for rubber plants.

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The ideal way to fertilize your rubber plant would be to mix organic and synthetic fertilizer at a gap of 6 weeks.

You can alternate the usage, which will save you on cost and provide your rubber plants with appropriate nutrients.

Is coffee ground good for rubber plants?

Yes, coffee grounds are good for our rubber plants. You must not use coffee ground directly on the plants.

It is best to make compost or liquid fertilizer out of it and occasionally use it on your rubber plant.

Coffee ground is a rich source of nitrogen, and they can help your rubber plant grow bushy and quick.

However, it is said that applying coffee ground-based fertilizer at an early stage of growth can stunt the growth of your rubber plant as it contains caffeine in it.

Thus, you must be aware of the same while using it on your rubber plants.

Also read: Do rubber plants like coffee ground?

How often should I fertilize my rubber plant?

Rubber plants need to be fertilized every 4-6 weeks. You need to fertilize them every 3-4 weeks during spring as they grow exponentially in size and lower the frequency as the growth slows down.

It is recommended to fertilize them only during their growing season i.e., spring and summer, and avoid any sort of fertilization during the winter months. i.e., during fall and winter.

If you fertilize them during the dormant season, the plant may not absorb any soil nutrients. However, the remains of fertilizer can harm the soil’s health, resulting in poor growth of your rubber plants.

Too much fertilizer in the soil is likely to affect its root growth resulting in root rot as well.

How do you fertilize a rubber plant?

Fertilizing your rubber plant is easy. You just need to keep the ratios right, and everything will fall into place.

The ideal fertilizer ratio must be 24:8:16 i.e., Nitrogen, phosphorous, and potassium, respectively.

You can use any fertilizer at a similar rate and provide it to your rubber plant during the growing season. Here are a few steps:

1. Pick an appropriate fertilizer and prepare half the standard dosage for your plants.
2. Mix the fertilizer(1/4th tsp. or approximately 1ml) into a gallon of water and water your plant as you usually do.
3. If you are using vermicompost or compost or any organic fertilizer, you can add a handful of it once a month or so.
4. Avoid adding more than the recommended dosage and do not fertilize the plant for at least two weeks after repotting.
5. Also, note that the soil must be moist before fertilizing. A dry soil could be a spell for disaster when it comes to fertilizing.

What happens if you over-fertilize rubber plants?

If you over-fertilize your rubber plant, your plant may give up on you.

But before that, your plants will show some signs, and it is crucial to look out for these signs and take necessary steps to prevent your rubber plant from dying out.

Now without further due, lets have a look at these signs:

• Yellowing and droopy leaves
• Root rot
• Stunted growth
• Excess build-up of fertilizer on topsoil.
• Change in the structure of foliage

Also read: Why is my rubber plant dying?

How can you save an over-fertilized rubber plant?

If you just found out that you have been overfertilizing your rubber plant and that is the root cause of all the problems, then its time to cheer up.

You have already achieved half success by identifying the problem.

Now its time to make things right, and that is not going to be too difficult if you keep calm.

Here are some steps you can follow:

1. Start by inspecting for signs of root rot and other similar problems.
2. You can clip the brown and dead leaves leaving behind fresh leaves and foliage.
3. The next step is to remove any excess fertilizer build-up at the top layer of the soil. For this, you can scrape off one inch of soil and replace it with fresh soil.
4. The next step is to water your rubber plant slowly but thoroughly. Watering thoroughly will remove any excess salt build-up from the fertilizers rejuvenating the soil back.
5. If you feel like repotting, you can give it a go as well.
6. Do not fertilize the plant for 6-8 weeks after following the above steps, and you must be good to go.

Also read: Root rot in rubber plant: Signs, causes and what to do

Conclusion

Does rubber plants need fertilizer? Yes, rubber plants do need some fertilization to absorb the nutrients required by them effectively. If your plants do not get the necessary nutrients, their growth will likely be affected, leading to various issues.

You can provide any NPK fertilizer in the ratio of 24:8:16, in the recommended dosage. You can also add a handful of organic fertilizers like compost or vermicompost.

Any kind of plant food should do fine as long as it can provide the appropriate nutrients needed by the rubber plant.

As far as the frequency of fertilization is concerned, it is recommended to fertilize the plant every 2-6 weeks depending upon the plant’s growth and the time of season you are fertilizing them.

Always remember the golden rule that Less is more when it comes to fertilizing a rubber plant.

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Sources: Fertilizer Application on Rubber plant, Nutrient management, Effect of fertilizer on rubber tree plant.