There are three questions I get asked regularly at this time of year:
- When do I remove my propagator lid?
- How do I water my chilli pepper seedlings?
- When do my seedlings need light?
So this video (and transcript below) is for all the new chilli growers out there.
Introduction to Chilli Seedling Care
Once your chilli seedlings have emerged from the soil, you guys have a ton of questions for me. I’m going to try and answer as many of them as I can.
When Should I Remove the Propagator Lid?
One of the most common questions I get is when to remove your propagator lid. The quick answer is as soon as possible after germination.
The long answer, unfortunately, we have many seeds, and they may germinate at different times depending on the type of seed, the plant variety, and the species. It could be a lot of different factors.
Understanding Plant Transpiration and Humidity
Plants typically breathe through their leaves, on the underside of the leaves, through pores called stomata. Now, if it’s too humid, it’s not able to do that effectively.
Another important thing to consider is the way that plants process water and nutrients. Each little plant, has developed a root system below the soil, and that root system is pulling in water as well as nutrients.
Then, the water is transpired through the leaves. If it wasn’t able to transpire that water, it’s going to stop pulling up as much water and therefore stop pulling up as much nutrients, which means you’re going to stunt the growth of your plants.
Now what happens when you’re in a humid environment it makes it very difficult for these plants to transpire effectively. There are two ways to fix this:
- firstly take off the propagator lid,
- secondly, use fans.
Now the fans will help strengthen these plants by moving them around, encouraging the stem to harden a little bit better, but more importantly, it will move the air around so there’s no stagnant stale air and these plants can not only transpire more effectively but they can also breathe more effectively.
You can open up vents on the propagator lids but they’re not very effective unless you can get some sort of airflow in there.
If you have vents on the side as well, you can create somewhat of an airflow in there if you can direct a fan in there or you can create some sort of convection current once a few of your plants have their first true leaves fully established. Then you’ve got probably a week maybe 10 days before you need to consider removing the lid.
What’s the Most Effective Watering Technique for Seedlings?
If you watch any of my beginner guides or most of my videos, I tell you to bottom water. The reason I bottom water my chillies is that when you top water you encourage algae growth. Whilst it’s not great for your chillies, it will go away after a while.
There are a couple of ways you could go about bottom watering. Either pour water directly into a tray and flood it to about halfway, then take out the seed tray and empty out the excess water after about 5 minutes because you don’t want it sitting in water. These roots need to breathe as well. Or, you can take a second tray, fill it to about half the depth of your seed tray – so that you can dip your seed tray without it overflowing.
The Importance of Water Temperature and Soil Preparation
Something else I wanted to point out, you want to make sure that this water is at the same temperature at least as your seedlings, and that’s because you don’t want to shock them. The same thing goes for soil when you’re potting up; you want to get that soil to the same temperature as the plants that you’re transplanting.
Think about this in terms of adding a goldfish to a new pond. You would make sure that the water that the goldfish is in inside the little bag is going to be the same temperature as the pond that you’re adding it into.
I’ve got my water bath set at 20° C, which is the same as my grow room. I have a little temperature probe in the water and that keeps this water at that temperature. I don’t leave it on all the time, I just switch it on a couple of hours before I know I’m going to be watering my plants so it doesn’t waste electricity. If you don’t have a spare heated propagator, you can just use a plain old tray with a heat mat underneath, and you can maintain the temperature that way.
Knowing When to Water Seedlings
Now I know that this tray is ready for water because it is very light. When you add it to the tray with water and it floats a little, it needs water! Stick your tray in the water for about 5 minutes. It will absorb all the water it needs, you can then take it out and put it back inside the original tray.
Whichever seedling containers you use, make sure that water can flow out and it doesn’t get blocked. If the water can’t escape, you’re going to end up having a cell that is just stacked with water.
Do my Chilli Seedlings need Artificial Light?
The third most common question I get is about lighting and more specifically when to turn it on. Chilli seeds do not need darkness to germinate, so you could effectively put your grow lights over them from the second you plant them. However, that’s just going to be a waste of electricity.
Chilli seeds, even the fastest ones, are going to take at least five days to start germinating, so on day five stick your light on. At the very least as soon as you see a little loop (chilli seedling stem) appearing, get your lights over your plants. If you’re using a sunny window sill, make sure that they’re exposed to the sunlight.
BONUS TIP: Feeding Your Chilli Seedlings: Do’s and Don’ts
A very important question is when do I start feeding my seedlings? The short answer is, don’t feed your seedlings. You do not need to for at least the first month. There should be plenty of nutrients inside your soil so that those plants can grow and spread their roots. After the first month, you’re going to be potting it up into fresh soil and a bigger pot.
If you do feed your seedling, which I know is very tempting, you might stunt its growth somewhat. If you are feeding your seedling, especially if you’re feeding it from the top there’s no reason for that root ball to spread any further. By not feeding it, that root system will look for more nutrients and it will spread, spread, spread. Then, by the time you do pot it up, you should have a very compact root ball that is well-established. When you pot up, follow the same practice for the first month to six weeks, depending on the pot size you’re going to, as the soil will have more than enough nutrients in there for that plant to do its thing.
Conclusion and Further Resources
I hope this answers some of your questions. If you have any other questions for me, let me know in the comments below.
There are some great articles to help you get started here: Chilli Pepper Growing
6 Stages of Growing Chilli Peppers for Beginners
Planting Super Hot Chilli Pepper Seeds: A Comprehensive Guide To Successful Germination And Growth
Germinate Chilli Pepper Seeds Like a Pro!
Everything you Need to Know about Light for your Chilli Pepper Plants
If you are still looking for chilli seeds, I have plenty available at chillichumpseeds.com. And, I hope that your season has got up to a fantastic start.
Hi. I am a little confused. Should the propagator lid be removed once seeds have germinated or once they have their first set of true leaves? Thank you
Like mentioned in the article and the video, ideally you want to remove the lid as soon as you have germination. Which would be great if all your seeds germinated at the same time. But you need to maintain warmth in the propagator until all seeds have germinated, so you would keep the lid on until then.