Question

Does seed germination takes place in the case of hydroponics ? if so how

Answer 1

Yes, seed germination takes place in the case of hydroponics.
Some techniques are used for this. I will explain below.

Techniques to Germinate Hydroponic Seedlings
In traditional gardening you can place seeds directly into soil to begin sprouting. However, in hydroponics you cannot place seedlings directly into the grow medium. They won’t take hold or they could be washed away by the nutrient solution. Instead you need to begin to germinate hydroponic seedlings externally from the hydroponic garden.
When you germinate hydroponic seedlings they need a lot of moisture in order to sprout. Seeds also need warmth (around 70 degrees or more) and bright light in order to be brought to life. To get started, it’s recommended to use grow mediums specially designed for seed germination. Rockwool cubes are good for this. They retain moisture and break apart easily to insert seeds.
If you’re growing multiple plants, you can create a “nursery” by placing several different rockwool cubes of seeds in a grow tray. Place the tray in a brightly lit area. Make sure to keep the grow medium moist while the seeds begin to sprout. You’ll notice sprouting a only a matter of days.

Transplanting Germinated Hydroponic Sprouts
Once the sprouts have reached about 3 inches in height and have multiple leaves, you’ll be able to transplant them in to your hydroponic garden which should already contain your grow garden of choice. You won’t even need to necessarily break the plant out of the rockwool. You can simply insert the cube directly into a hole in the grow medium of the garden.

Post-Transplant Care Techniques
It’s recommended to water the plants from the top with your nutrient solution for the first week. This will prevent them from drying out and will give the roots time to grow downward.
Remember not to place your artificial lighting too close to the newly sprouted plants. You don’t want to burn them. Start grow lights up high and then lower them incrementally week by week until they are at the appropriate height – approximately two feet away from the plants.