Seedlings need water, but too much can cause a whole host of issues.
You want the soil around a seedling to be damp but not wet. Letting it dry out every now and again is no big issue as long as the plant doesn’t start to drop.
Yellowing leaves, stunted growth and drooping plants can all be signs of overwatering.
If your seedlings look a little unhealthy and you have been constantly watering them then maybe hold back, let the soil dry out a little and see if they perk up.
4. Not Providing The Right Environment
Different seeds need different conditions in order to thrive. Many people think seeds are seeds and start them off the same way, but this isn’t the case.
Some seeds like lots of heat and humidity in order to germinate, while others will only germinate when the temperatures or cold.
You need to look this up on a plant-by-plant basis and find out how they like to grow. Your seed packet should have all the info you need, but it not then the answer is only a google search away!
5. Too Much Heat!
Too much warmth from being indoors, coupled with insufficient light, causes leggy seedlings, as you can see above.
They are growing quickly but not strongly and can support their own weight, leading to them flopping over. If your plants are under lights but still growing like this, the conditions might be too warm for them.