How Do You Know If Your Bonsai Seedlings Are Healthy?

If you are new to growing trees from seed, you may not know if your seedlings are healthy or not.

It is pretty important to know this, as you need your seedlings to grow strong enough that you can start applying bonsai techniques to them.

I will go through some things you can look out for so that you know if you are on the right tracks, but to be honest, you do not need much experience to look at a seedling and know if something is wrong. It will be very obvious if it is not healthy.  

What Species Are You Growing?

Knowing what species you are actually growing is going to be very helpful to understanding if you tree is healthy or not. Knowing what the tree should look like and what is considered normal for that species is always a good starting place. 

Knowing what you are growing is also going to help with your expectations as different trees grow at different speeds and are going to look very different at certain points compared to others.

You have to remember that in general trees are very slow growing, especially when you start comparing them to other plants like vegetables. A tomato plant may end up being 6 foot tall after a few months, where as a tree may not even be 6 inches after the same amount of time. 

(You can read more about – How Do You Care For Bonsai Seedlings?)

Have Your Seeds Germinated Yet?

If you are starting a bonsai from seed, the first thing you need to do is to get the seeds to actually germinate.

This can take a bit of effort and be a slow process, but it will really depend on what species you are growing. You should be able to look up what is expected for the species and then you will know roughly how long things should take to happen.

You should start to see some signs of life in the expected time period, and this is your first sign that your seedlings are healthy and doing what they should be.

(You can read more about –  What To Do When Your Bonsai Seeds Are Not Growing)

Are Your Seedlings Putting on Growth?

One of the easiest ways to understand if your seedlings are healthy or not is to just look at their growth and their progress. If they are growing, this is a pretty good sign that everything is okay.

You want to see that your little tree is slowly getting bigger, there should be more leaves and generally everything should be slowly and steadily expanding outwards over the first few months. You should also see new buds slowly swelling at the tip of the seedlings, getting ready to open up into even more leaves.

It can be a little hard to tell if anything is happening at times, so taking photos is always a good idea, then you can check every few weeks and see if it is making progress.

Are They Long and Leggy?

If your seedlings look long and leggy, as if they are stretched out and there is quite a lot of space between each pair of leaves, then this isn’t ideal.

This is usually from a lack of light, so you will have to find a way to give them more, which means you need to move them.

You want the growth to be short and compact, even though this means the tree is shorter, it is healthier.

They Shouldn’t Be Falling Over

Another sign that something is wrong is if your seedlings are falling over. They should be able to stand up under their own weight.

Sometimes this happens due to them being over stretching I just mentioned above. They get too long and start to fall over.

However, if you are noticing an issue at the base, such as it is going soft of even drying up, this is a problem. Your seedlings may have a disease called “damping off” and unfortunately it is fatal, so you cannot do anything about it.

So really, the more rigid and upright your seedling looks, the better. 

Do The Leaves Look Healthy?

Looking at the leaves of your seedling is a very easy way to tell if it is healthy or not. They should just look healthy, which sounds very vague, but I assure you, you will know when a leaf doesn’t look right.

They should be properly formed and fully opened. They shouldn’t look strange or curled up. They should also be a good size. Of course they are going to be small, it’s a tiny seedling, but should be able to look at them and think they are a nice healthy size.

This is also why you need to know what species you are growing, as the leaves of one tree are going to look very different to the next, so it is important to know what they should look like so can understand if they are looking right or not.

Also it is important to remember the first leaves of a seedling always look the same, no matter what plant it is. You have to wait until the next set of leaves open, which are called “the true leaves”. It’s these leaves that you have to look at to assess if they are healthy or not.  

Are The Leaves A Healthy Colour?

A huge indictor of the trees health is the colour of the leaves. They should just have a healthy glow and it will be very obvious if they do not. They should not be pale, yellow or even brown, this is generally a bad sign.

Also you need to remember that some leaves are a slightly different colour when first they open. They may actually be a little pale, or even reddish …let them open and stretch out before you panic as it can take a few days for them to reach their proper colour and look healthy.

Although I would argue that you can still tell if the leaves are healthy or not in this state, you can just tell. It’s like looking at vegetables, you can tell what ones are healthy and delicious and what ones are maybe a bit sad and tasteless.

Is There Any Mould Growing?

If you see mould growing, it can be quite worrying. Often it is pretty harmless; but it depends where you see it.

If you see the mould on the soil, it is not too much of a worry it just means that the soil may be too wet and you should try and adjust your watering, or increase your airflow.

However, if you see mould on the seeds, or on your seedling, this is something to worry about and this could end badly.

(You can read more about – What To Do About Mould On Seedlings)

Are There Any Pests?

You ideally do not want to see any pests on your seedlings. They are very delicate and are going to struggle to handle an attack and will probably die.

It is going to be best to try and keep the seedlings separate from your other trees to avoid any contamination, but I know this doesn’t always help. However, I would say that pest infestations are quite rare in seedlings, but not impossible.  

Although, you may notice two common “pests” that are not really an issue. You may notice little tiny bugs walking around your soil and jumping about. These are springtails.  They are not actually pests, they are going to be eating any decaying matter in your soil, so they are fine and should be left alone.

The other thing you may see is little flies swarming around your seedlings. These are usually fungus gnats and usually show up when the soil is too damp. They are annoying, but totally harmless. You can just try and adjust your watering to see if you can get rid of them.

Are You Using Good Soil?

The health of your seedlings can be linked to the soil that you use. While you can grow seedlings in practically anything, some soils are going to be better than others.

If you have seen my video on my “Grow It Bonsai Kit”, you will have seen the soil that comes with this kit is that coco peat stuff, and while it works, it is not great. It holds too much water and it can be very easy to make things too wet and the seedlings can basically drown.

I always suggest using very fine bonsai soil. This will be light and airy and should be able to give your seedling all the right conditions for success.

However, if you have started your seeds in some soil that you think is maybe not ideal, it’s okay. You just have to manage the situation and make sure they are well looked after until they are strong enough to put into better soil.

I also wouldn’t rush this, as disturbing the roots can be very damaging and stressful for a seedling, even if you are trying to help it out by giving it better soil. Sometimes it’s better to just manage what you have until the tree is strong enough to move it.

(You can read more about – A General Guide To Bonsai Soil)

How To Make Sure Your Seedling Stay Healthy

It’s easy to spot when your seedlings are not healthy, but it is more difficult to know exactly how to care for them properly and keep them healthy.

Really it all comes down to checking on them daily and making sure they have enough water and light as well as airflow.

Don’t worry about fertilising them or trying to do bonsai work on them. For now your job is to just get keep them healthy and to get them strong, then you can do the work.

(You can read more about keeping them healthy – How Do I Care For Bonsai Seedlings?)

Conclusion

As you can see there are a lot of different things you can look out for that will help you decide if your seedlings are healthy enough.

So long as you are caring for them properly you should have very healthy trees that will quickly grow and become strong enough to work on as bonsai.

(You can read more about – What Are Some Common Mistakes Made When Growing Seeds For Bonsai?)