Shock to small seedlings can undermine the entire crop cycle. Autoflowers are especially susceptible.
1. Overwater/underwater your plants.
2. Overfertilize/under-fertilize them.
3. Expose them to extreme temperatures. Pay extra attention if you are using black seedling trays as pockets of air can heat up and harm the delicate roots. Consider using shade cloth in hot climates.
4. Allow your transplants to become rootbound.
5. Handle them roughly during the transplanting process.
6. Transplant them too late in the day under sunny or hot conditions.
7. Expose the roots to light for longer than necessary.
Following these precautions will help ensure optimal health and growth for your autos.