Q.Growing Lettuce from seed
I sowed some lettuce seeds on Feb 18, which germinated 3 days later in the house. They would now be about 3 inches (8 cm) tall but for the fact that their stems are very thin and fragile and they are lying horizontal. Do you have any idea what has caused this and what I could have done to make them grow straight with firmer stems?
It sounds as if you have some leggy seedlings, which are caused by a lack of light. The light source is too far away and your plants are speeding up their growth in order to get close enough to it. This causes the seedlings to get thin and floppy.
I would advise you to move your seedlings to a south-facing window so they get maximum exposure to the sun.
The article below will give you some pointers on how to toughen up your seedlings, such as brushing your hands over them a few times a day or gently blowing an oscillating fan on them a few hours a day.
Try moving your seedlings to a south-facing window You can also force seedlings that are too tall to grow thicker by lightly brushing your hands over them a few times a day or placing an oscillating fan to blow gently on them for a few hours every day.