Begonia Grandis – Best Ways to Care for Hardy Begonia

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Did you know that in the “floral dictionary” Begonia means “be cautious” but it can also be a symbol of gratitude and respect? As numerous as those meanings, begonia plants are often kept at homes, mainly for their colorful flowers. In today’s guide, I’m going to introduce you to one of the loveliest members of this enchanting family- Begonia Grandis AKA Hardy Begonia.

Care guide highlights: Begonia Grandis needs soil rich in nutrients, which can retain moisture but is well-draining at the same time. This Begonia prefers shady locations, so avoid exposing it to direct sunlight. It can survive lower temperatures, but when it comes to humidity, higher is what Hardy begonia needs. Being a flowering plant, it requires more frequent watering, but be careful not to overwater it. It can be propagated via seeds, tubulars and cuttings.

Here are the topics we shall talk about here:

  1. Soil requirements for Hardy Begonia care
  2. Light requirements
  3. Begonia Grandis water requirements
  4. Temperature and humidity
  5. Fertilizing
  6. Repotting and pruning Begonia Grandis
  7. Begonia Grandis propagation
  8. Common problems of begonia Grandis care
  9. FAQ

Before we proceed with Begonia Grandis care guide, take a look at other lovely members of the family:

Soil Requirements for Hardy Begonia Care

The soil you feed your plant with is always the most important factor to pay attention to in the care and maintenance routine.

If you should mess up with this one, then getting all the other factors right won’t do any good.

This is all the more so important when it comes to Begonia Grandis, AKA Hardy Begonia.

The fleshy beauty we are talking about here likes to have its soil rich with food.

So, if you were to choose some sandy mixture, think again!

Begonia Grandis needs soil which is rich in nutrients

Adding a little sand could be an option if you want the soil to dry faster, but with your Hardy Begonia this should not be the case. Perlite, perhaps.

B. Grandis likes its soil to have well-draining properties and to keep moisture, at the same time. As a consequence, the soils that dry out too fast are never a good option for Hardy Begonia.

Accordingly, always go for organic soils rich with nutrients so this late bloomer can have the right growing conditions.

If it happens that you made a mistake and chose not so great a soil, try improving and fixing it with some compost, but we’ll get to that.

Light Requirements

After you make the right soil choice (funny how we always think about the pot (color, size, material) first, and choose just any soil that comes our way?), it’s time to think of light requirements or, the spot where you’ll keep your Begonia grandis.

Naturally, you might think this Begonia will ask for plenty of sun, being a flowering plant and all.

But, guess what?

You are wrong (but, just partly!).

Far from saying you have to keep it in a completely dark room, but you can’t allow direct sunlight exposure either.

That would be detrimental to the leaves, flowers, etc., etc.

begonia grandis light requirements

Instead, let’s try to find the middle ground, the buffer zone, or call it whichever you like.

Dappled and shaded spots would be the ideal choice if you want to provide the optimum light conditions for your Hardy Begonia.

This will be the best condition for our gentle perennial of bright green leaves shaped like a heart. In such a light condition, its fragrant flowers will keep their proper pink or white color, without discoloring or spotting.

However, if for some reason you do not have such a spot in your apartment, improvise then.

Cluster some large sun-loving plants and put your begonia in their midst so they can provide the natural shade to Hardy Begonia.

Such an establishment will resemble a small jungle of your own that is pleasing to the eye and will make Begonia Grandis keep thriving, which is the point.

Begonia Grandis Water Requirements

Which reminds me, I’m thirsty!

Just like (almost) any other plant in the universe, our lovely beauty of dangling flower clusters is so keen on water.

It even prefers its soil wetter (not moist, wet) than dry.

Accordingly, you must pay attention to the proper watering schedule.

Flowering plants need more water so they can adequately satiate the stems, the leaves and the flowers too.

Pay attention to Hardy Begonia watering schedule

Don’t tell anybody, but I messed up my darling African violets. I skipped watering for a couple of days – completely lost track of time – and the result is that the flowers that were there dried up and new ones haven’t appeared yet. And, it’s been three weeks already. The worst thing of all – I kept them flowering throughout the winter just to mess them up now!

So, don’t make the same mistake as I did with my violets.

On the other hand, don’t overdo it either.

Water-logging won’t bring any good. It will just make the roots sit in water, starting to rot rather soon.

I presume you understand where your Begonia Grandis goes from there, right?

We don’t want that.

If you aren’t sure if it’s time to water, there is a simple check you can make.

Lift the pot from the tray to look for water clues. If none, it’s time to water!

In addition, you can try sticking your finger, or a toothpick even, down from the top surface (an inch to two deep). If you feel it’s dry or the toothpick/ finger is dry when you take it out – that’s your cue.

Your Hardy Begonia craves water.

Give it some!

As is the case with other flowering plants, you can cut back watering once the flowering season ends and the dormant season starts. This is where Begonia Grandis is rather special (will explain later).

In any case, begonia will sustain (not to say, tolerate) an occasional dry period, but try not to have too many of these. It will just stress the plant unnecessarily. Should you do that, NEVER compensate by adding tons of water.

Just water normally and let the plant recover from the dry spells you caused (that’s what I’m still doing with my poor violets).

Temperature and Humidity

These two always go together.

Probably it’s because they are co-dependent.

In any case, let me first deal with the…

begonia grandis Temperature and Humidity

Temperature Requirements

Did you know that Hardy begonia falls under the “Asian” species?

It originates from China and can also be found abundantly in Malaysia and Japan.

Accordingly, the best temperature and humidity conditions for the Begonia grandis are the ones that resemble those in Zones 6-9.

However, and as a far stretch, to be honest, if you mulch it good in autumn and keep it like that during winter it can even survive in Zone 5.

So, what am I saying here?

I am saying that your begonia grandis will survive even when exposed to temperatures as low as 23°F. Remember, it’s HARDY Begonia we’re discussing here!

Although, as we are not discussing outdoor care, then you needn’t worry about this.

When inside, just give it “normal” room temperature. For the unaware ones, it’s 65° and 75°F (18° – 24°C) I am talking about.

On the other hand, as for…

Humidity Requirements for Begonia Grandis

Here, the situation is a bit specific. Begonia Grandis thrives in humid conditions.

The best you can do is imitate tropical and subtropical environments. Cause, that’s where this Begonia plant comes from.

If the space where you keep it is drier, misting will greatly help improve the humidity and besides it will make the leaves and flowers shiny and lush and appearing healthy overall.

Frequent watering will also have a positive effect, but be cautious here not to cause more harm than good.

Finally, if you can’t be bothered thinking whether this or that amount of water is too much or too little, then simply use a humidifier to improve the humidity of the space designated for the Hardy begonia.

The natural conclusion here is that the use of the air-conditioner should be reduced to a minimum in the room where you keep begonia grandis. It will just dry the air out unnecessarily.

Besides, the air current, or draft, might cause the delicate flower petals to fall off, so here’s another reason to keep it away from the air-conditioning.

Begonia Grandis requires higher humidity


Fertilizers can just as well be omitted in the care routine for Hardy Begonia.

As long as you mulch it over the winter and add natural compost in the spring, it will grow just fine.

If, however, you are not able to find natural compost, which is often the case, you can go for a liquid fertilizer (10-10-10). Careful when mixing, cause you do not want to add too much of it.

You might think the more the merrier, but it ain’t so.

The optimum mix is 1 part fertilizer and 3 parts water. Once you prepare the mixture like this, pour it around the base of the plant.

Again, spring is the time to fertilize and there will be no need to repeat it until the next season.

Be careful not to overfertilize Hardy Begonia

Repotting and Pruning Begonia Grandis

These two may seem irrelevant sometimes, but think again?

How would you feel if you didn’t cut your hair for a longer period of time? Yes, it would grow, but, what would be its quality?

Accordingly, let us check when you repot and prune Begonia Grandis regularly.

Repotting and Pruning Begonia Grandis

Repotting Hardy Begonia

All plants outgrow the original pots; this is a fact.

This does not mean you should throw or give the plant away.

Instead, you can repot.

This is an important step in the proper maintenance of the plants.

Here’s a little something you need to know before I tell you the benefits of repotting.

Namely, Begonia Grandes rarely grows larger than three feet wide or high. Moreover, the plant will take five years to reach its full size.

All of this means repotting is not that crucial a step.

Still, once the soil in the pot has hardened, we can all agree that it’s time to repot.

Or, when you notice that the roots have nowhere else to go, then it’s also time to repot your Hardy Begonia.

By the way, this is the perfect time to bring some color into your life!

I like to play with pot colors so I am always choosing different ones. For example, the drapes and sofa covers in my living room are vine red and the rest of the furniture is neutral. So, I went for orange pots. The contrast to both prevailing green in my plants and the dark red covers and drapes is exquisite!

Other than color choice, you know that you have to go for a pot larger than the old one. As for the pot material, try to go for one that will provide good air circulation and water drainage.

As a hint, always go for the pot with holes at the bottom and an adequate collecting tray. In this way, the excess water will freely run through and you can pour it out from the tray avoiding root rot.

Once you repot, the new soil will enable the roots to grow, feeding Begonia Grandis more nutrients than before.

Related: Picking the Right Pot for Indoor Plants- 6 Rules

I will not go into the details of the procedure, cause I believe you know how it’s done – wash the new pot, put some soil inside, spray it with water, carefully extract the plant from the old pot, place it evenly into the new pot and keep adding new soil until you’ve fully covered the roots.

Shake a few times in the process to eliminate air pockets.

And, that’s about it!

Repot Hardy Begonia when current container is too small


When it comes to pruning, there’s no philosophy here either.

Just pinch out the leaves that seem damaged before they infect the rest of the branch.

More importantly, pinching out the fading flowers is what you simply must do.

In this way, you will relieve Hardy Begonia of the unnecessary burden such as feeding still the flowers that are already dying.

As a benefit, all the nutrients will be redirected to the new blooms tuning into beautiful white or pink flowers that you can enjoy all the way from July to late into the autumn.

Begonia Grandis Propagation

Whenever we get a new plant, we are immediately checking how to reproduce it.

And, how happy we are when we figure out that a plant can do that on its own. This is exactly one of the surprising traits of Hardy Begonia.

Practically, this Begonia is indestructible. Even if it completely decomposes over winter (!), it grows back in the early spring as if nothing happened. 

Probably, hence the name Hardy Begonia.

Remember how I sad paragraphs ago that Begonia Grandis is special?

Seriously, as the wintertime is approaching the leaves on your Begonia Grandis will start falling off and the whole plant will start turning into an unsightly pile of death.

Begonia Grandis Propagation

Whatever happens, resist the urge to clean this up no matter what- be patient, it will pay off.

Just leave it like that and witness the resurrection of Begonia in the late winter/early spring.

I mentioned mulching previously and I know it’s typically done for the outdoor plants, but it can’t hurt for the indoor ones, right?

On the contrary, it will preserve the warmth during cold winters and help the plant survive.

As for this regeneration process, I was curious so I asked around. The point is that Hardy Begonia develops teeny tiny bulbils on its upper leaves (in their axils, to be more precise). As the plant starts falling apart in the late autumn, so these nascent tubers fall to the ground forming a brand new plant next spring.

Now, I know you would like to have another Hardy Begonia in your home, so here are a few things you can do to actually propagate it.


If you are that idle, collect the seeds by letting the pods dry on the plant and then separate the seeds. Let me tell you right away – it’s as long a process as it is a tedious one, so you may just as well skip it.

Trust me. Skip it!

Begonia grandis seed capsules


These are the easiest way to propagate. Separate the tubulars and place them in the new pots. The final result is a whole new Begonia Grandis!!


Why, of course. Equally successful as propagation with tubulars. Take a leaf or stem cutting, place it directly into the soil and wait for the new plant to start growing. Or, you can place them in water and wait for the cutting to develop stems. Then you can proceed to transfer the cutting into a new pot.

Common Problems of Begonia Grandis Care

Pests is your answer.

Seriously, when caring for a begonia grandis you will more likely come across pest problems than anything else.

As you could see from the article, the care steps are rather simple, so there should be no major problems.

Just pay attention to watering since that can be a good pre-condition for bugs.

On the other hand, watch for thrips, mealy worms, whiteflies and mites.

Without much fuss, you can deal with these using insecticidal soap mixed with water. Just spray the pests and watch them disappear for good leaving your plant nice and shiny again.

Another option is to use neem oil on your Hardy Begonia leaves to prevent the pests from appearing in the first place.

Hardy begonia common pests

Frequently Asked Questions

Before the final word, there are a few more facts I would like to share with you.

These are related to some of the most frequent questions people have regarding Hardy Begonia, so let me break it down for you.

Should I mist Begonia Grandis?

Yes, you should. As said, regular misting will only bring benefits to your Hardy begonia. First off, it will feed the leaves with water directly. Next, it will boost the humidity conditions in general, as Hardy Begonia is known to like higher humidity conditions.

Why are the leaves on my Begonia Grandis curling?

There are two possible reasons. One is water-related and the second has to do with light. For example, if the water you are using for watering is of poor quality, this can lead to curly leaves on your Begonia. Also, overwatering is the most frequent cause of the curved leaves on Begonia Grandis. Moreover, too much light can also cause leaves to curl. Remember, shade is the right light requirement.

How do you make Begonia Grandis bushy?

If you like your plants wider than taller, Begonia Hardy included, just cut out the long stems. Of course, you will have to use clean shears so as not to infect the plant.

How do you know when Begonia Grandis needs water?

You will know it’s time to water when the leaves start drooping and the flowers dry suddenly. But, try not to let it go that far. Check the top layer of soil daily during summer to see what is happening. Being a flowering perennial, it will require plenty of water so make sure to keep a tight watering schedule.

Is Begonia Grandis toxic to dogs?

Believe it or not, yes, it is! Swallowing a plant part might cause severe salivation, intense burning and mouth irritation in your dog. Make sure that your precious Begonia is as far away from your precious pet, cause these two don’t get along well.

Can you propagate Begonia Grandis in water?

Yes, you can! If you decide to propagate Hardy Begonia with stem or leaf cuttings, you can place the cuttings in the water and wait till they develop roots. After that, you can transfer the cutting into a pot with fresh soil and you’ll have another lovely begonia Grandis to admire.

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