Now that you have made the right decision to grow with hydroponics, the first thing you need to do is get some seedlings started. Just remember that you should always start your seeds in a hydroponic medium and nothing organic. This will ensure that there will be no complications with your hydroponic plants later on. Keep everything as sterile as possible when it comes to your hydroponic system, even when transplanting and adding seedlings.
Start by selecting a growing medium. Rockwool cubes tend to do best as they can be easily transplanted into any hydroponic system.
Press the seeds into the rockwool and ensure they are moist
It is a good idea to keep the rockwool cubes in a grow tray so that you can easily fill the tray with water and then drain, as required.
Germination of a seed takes place when the proper amount of moisture, air and heat are present. A seed can crack and start germinating anywhere from a day to two weeks – it just depends on the specific plant you are cultivating. When placing the rockwool cubes into the tray, make sure that the rockwool is spaced apart in order to ensure proper air exchange for the seedlings.
Whenever growing with hydroponics, it is always a great idea to always have a germination box/humidity dome for starting seedlings, to encourage germination, and to create clones. You could start your seedlings directly in your hydroponic system, but the failure rate for germination will be drastically increased compared to starting them in a humidity dome. So do yourself a favor and get a humidity dome for germination (or with a little effort, you can even build one yourself) – it will last longer than you think.
For the next one to three weeks, it is critical to keep the moisture level high and, for the first few days at least, at a rate of 70%, if possible. A high moisture level in the air is always going to be important for healthy growth since there is no root system to support the seedlings. Keep the seedling in a constant state of moisture, even if you have to take a spray bottle and lightly mist them a few times a day.
After a few weeks, it is time to transplant your seedlings into your hydroponic system. First make sure that there is proper root structure coming from the bottom of the rockwool if the roots are too small, they will not be able to reach the nutrient solution. When placing in your hydroponic system, be extra careful with the roots as they are delicate and can break very easily. Once the seedlings are in place, just keep them lightly misted every so often for a few days after transplanting.
For the next week or so, keep a close eye on your newly transplanted seedlings because, as a result of the transplant, they will now be taking in a nutrient solution. Some types of plants handle this better than others. If you see your seedlings getting dying off, then try to reduce the amount of nutrients in your water reservoir for a week, then refill and put your hydroponic plants back in place.