How to Transplant Chilli Seedlings into Tube Pots for Greenhouse Growth

Here at Hot Chilli Mama Farm, we've had great success with germination so far with well over a 80% strike rate. So now we have plenty of seedlings that are ready go to the next step, which is repotting into tubes and into the greenhouse. So here is a description of how we go about that.

Step 1: Check if They’re Ready

Before transplanting, take a close look at the seedlings. They should be around 4–6 cm tall with two or more sets of true leaves (the ones that appear after the first baby leaves). The stems should look upright and firm. If they’re a bit thin or leggy, keep them under lights a few more days so they can strengthen up. At this stage we weed out the weaklings, even if they grow they often don't produce well.

Step 2: Prepare Your Tube Pots and Mix

Tube pots (around 5–7 cm wide and 10–12 cm deep) are perfect for young chilli plants — deep enough for strong root growth without taking up too much space. Use a light, airy potting mix made from:

• 60% quality compost or potting mix

• 30% coco coir or fine peat

• 10% perlite for drainage and aeration

That touch of perlite is important — it keeps the mix open, prevents soggy roots, and allows plenty of oxygen to reach the developing root system. Mix everything together thoroughly so the texture is even.

Step 3: Transplant with Care

Water your seedlings about an hour before transplanting to help ease them out of their trays.

• Use a small spoon or dinner knife to lift each seedling gently, keeping as much of the root ball intact as possible.

• Fill each tube pot about three-quarters full with the potting mix.

• Make a small hole, lower the seedling in and gently firm the mix around it.

• Water lightly to settle the soil around the roots. We include 10% Seasol in this first water as it is a tonic and helps minimise transplant shock.

Step 4: Move to the Greenhouse

Once potted up, place your seedlings in a bright, warm greenhouse with good airflow. The airflow is not only good good for plant health, but also helps create strong stems and branches which are important for withstanding winds and carry loads of fruit. Keep the temperature between 18–25°C and protect them from harsh direct sun for the first few days while they adjust.

When the top of the mix starts to dry out — moist but not soggy is perfect. After a couple of weeks, you can start feeding lightly with a diluted liquid fertiliser or worm tea every 10–14 days to encourage steady growth.

Step 5: Grow On to Around 20 to 30cm

In the greenhouse, your chillis will start to flourish. Rotate the pots every few days for even light and trim off any yellow or weak leaves. We also trim off the lower branches so that we get a single strong stem, which makes tying them up much easier and helps support your fruit. We then let them grow on until they’re about 20 to 30cm tall with strong stems and a well-developed root system.

Step 6: Harden Off Before Planting Outside

The next step will be to harden your seedlings off before planting. We will take you through that process when we get there.

Final Tip: Set Your Chillis Up for Success

By using a good compost-and-perlite mix and giving your young plants time to grow strong in the greenhouse, you’ll set them up for success. Healthy seedlings mean more flowers, more fruit and more heat when harvest time comes. Happy growing — and may your chillis be hot, healthy, and full of flavour!