In order to germinate, plants need the moisture level to be consistent, they need to stay warm, and as soon as germination happens, they need light.
In order to ensure our plants get enough moisture and heat to germinate, we do one of two things. If the seeds are sown directly into the planting container, we cover them with a garden cover. If the seeds are in peat pellets, we have the pellets in a tray and then we cover that tray with a plastic dome.
Check your seeds regularly. If they are drying out, carefully water them to keep the soil or the peat moist. You want to ensure that you don’t disturb the seeds, while giving them adequate water to aid germination. 
Water softens the seed coat so that the seed can germinate. The environment for the seed needs to be moist without being too wet. If the seeds’ environment is too wet, the seeds can rot before they germinate. Likewise, once they have germinated, too much water can cause problems with the roots and result in unhealthy plants. Make sure seeds in peat pellets are not in standing water.
Temperature is also important. Seeds need warmth to sprout. Try to keep the temperature between 18 and 25 degrees Celsius. Keep your seeds away from any drafts.
Once you see sprouts, make sure you move your new seedlings under the light. Remember, if you have an LED light, keep it about 10cm above the plants. If you have a metal halide bulb, you’ll want to be 30cm away. At this point, you will remove the garden cover and let the soil surface dry out between waterings. This will lead to stronger roots. You can leave the dome on the peat pellet tray because it is clear and the light will penetrate to the growing plants.
Germination Problems
There are many reasons that seeds might not germinate. The two most common are that the environment was too dry or the seeds were too old and no longer viable. However there are other reasons seeds fail to sprout.
Most common reasons for germination problems:
- Wet soil, seeds rotted
- Soil was too dry
- Temperature was too low
- Seed is no longer viable (Want to test if your seeds are viable? Do a quick germination test!)
Once your seeds have germinated, it’s time to transplant!
Teaching From the Garden 