Fertilisation after seed starting

How much do seedlings need?

Many people think Chilli seedlings need fertilisation straight after they have germinated . Nothing could be further from the truth. Chilli seedlings need far less fertilisation than most people might think.   After seedlings have germinated, they only need additional fertilisation once they develop their first set of true leaves. But even then, the amount of fertilization required is negligible. Once the true leaves have developed, the plant will start getting nutrition from photosynthesis. As the seedling develops its true leaves, the plant will also start expanding its root system to help extract nutrients from the soil.

Once a seedling reaches this stage, I feed them half strength Chilli Focus (2.5 ml per litre). I start doing this as soon as I pot them on for the first time. When the seedlings get to two to three inches tall, I pot them one again. After this, I will up the dosage of Chilli Focus to 5ml per litre of water.

I continue feeding the seedlings at this dosage (every second watering) until they are ready to be potted on again. At this point, they will be three of four inches tall and have about four true leaves. It will stay in this pot (normally one litre) until they’re ready to be hardened off. Hardening off normally takes place in middle to late May

Fertilisation after potting on

Setting the scene

This season, because I started my seeds earlier, my seedlings will stay in pots far longer than they might have done in the past.  This will have knock-on ramifications that need to be considered.  To consider these ramifications, let’s go back

Okay, so I started seeds in mid-January. The seeds germinated after seven to ten days. After that, the seedlings took two weeks or so to develop their true leaves. They were potted on for the first time. It then took another two weeks for them to reach the size where they needed to be potted on for the second time. Finally, let’s say after another three weeks they were ready to be potted on into the one litre pots. The scene has been set

In total, it will take about eight weeks for the seedlings to be potted on into the one litre pots. The estimated time now would roughly be the middle of March. There will now be two and a half to three months before these plants will be hardened off

You might say – Whoa. Hold the lorry, that’s a long time for plants to be in a single pot without their potting soil being replenished.  Correct, this is where we need to be careful.  While the plants were being repotted quickly at various intervals in the initial stages, once they get into litre pots, this will no longer be the case. Where the plants were able to extract nutrients from the potting soil (by extracting from nutrients in the mix and low dosage Chiili Focus ), this will become more difficult. Nutrients in the pot will become depleted, and the plants will start struggling with nutrient deficiencies. This is the point where we need to start upping the game.

Previously, when I might have started my plants later, this would not have been a problem. I would have only been potting the seedlings into one litre pots in say May.  They were comfortable only getting Chilli Focus a 5l per litre for the six weeks leading up to hardening off, but that now will have changed. My Chilli seedling fertilisation now needs to be approached in another way


When the past meets the present.

It was while thinking this through that a vision came to mind of something that happened to me five years ago.  I avidly remember a massive Chilli bush that I had grown. It was ever so lush and green. It was the picture of health. The only problem was it didn’t want to flower.  I couldn’t figure out why, but after digging around the internet, I finally realized what had happened. I had fed the plant nitrogen for too long.

In those days, I used chicken manure to prepare my pots for final potting on. Chicken manure is an excellent source of nitrogen. Obviously, in that particular pot, I had put too much in and/or the fertilizer I used afterwards had high levels of nitrogen.

Now, if a plant gets a steady source of nitrogen, it will devote all its energies to growing as big and strong as possible. After all, in their natural habitat, Chillies are perennials. They don’t necessarily mind growing into a healthy plant in one season, and then producing fruit in later seasons.

And this is precisely what had happened with this plant. It had no idea that I was in a race against time for it to produce fruit and ripen in one season. It was enjoying the excellent growth enhancer I had provided it with.

Needless to say, I didn’t get a single pod out of the bush that year, but a lesson had been learned- don’t give you plants too much nitrogen. It can definitely be given to them when they are still developing into bushes in the seedling stage. However, once that is achieved, nitrogen should be limited. Fertilisation should then be changed to favour other stages of development, like blooming and fruit set. This can be achieved through fertilisers with higher levels of phosphorus and potassium

Back to now. So how could I use this experience in my current Chilli seedling fertilisation when they get into one litre pots? I need to change to a more potent fertilizer to cope with nutrient depletion, but I could also use the opportunity to increase the amount of nitrogen I normally give to my seedlings. In this way, I could encourage growth before they are finally potted on into their final pots.

To achieve this, I started looking for a fertiliser that would meet what I wanted to achieve. I finally settled on a liquid fertilizer with an NPK of 7-3-5.  Chill Focus, by comparison, has an NPK of 2.7: 1: 4.4. So, it is upping the game somewhat. I will feed the Chilli seedlings with this fertiliser until I have hardened them off. I will then change to another fertiliser to prepare the pots in which the plants will spend the rest of the season.


I don’t want to throw all my eggs into one basket. After all, if this fails, it will be a disaster. With this in mind, I will continue to fertilize with Chilli Focus for some of my plants in the normal way.

I have also decided to use the opportunity to try something else. I want to compare Chilli Focus against tomato feed and seaweed extract.  These are fertilizers that other growers swear by.  I want to use them side by side against Chilli Focus to see which comes out ahead. That, however, is the subject of an upcoming post

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Fertilising Chillies


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