When starting a hydroponics system, growers have a choice to either purchase seedlings or start pants from seeds. There are many benefits to starting plants from seeds even in hydroponic systems such as lower cost, less chance of disease, and wider variety of species.
When starting seeds hydroponically, many guides recommend using rockwool, starter plugs, or some other fine growing medium. This medium is then placed in a net cup and surrounded by hydroton.
In order to make this process more simple and keep costs lower, I decided to try starting seeds with just hydroton. I also used tap water and didn’t measure pH levels since I really wanted it to be an incredibly simple process.
So can you start seeds in hydroponics with hydroton?
Seeds can be started in hydroponics by simply dropping the seeds in a growing medium. Many hydroponic growers recommend using starter plugs or rockwool which will help increase the odds of seeds germinating. However, a net cup filled with expanded clay pebbles that sits in water will also work at starting seeds. The seeds cannot be floating in the water otherwise the chances of germinating are low. Seeds prefer to rest on a moist growing medium so that the seed can draw moisture in as needed through capillary action.
As you can see in my photo, I was able to germinate Tomatoes, Chard, Lettuce, and Peppers with just net cups, hydroton, and water.
Here’s a video walk through of starting seeds in hydroton:
Tap water without nutrients is fine to start seeds. Once the seeds sprout then the plant will need to absorb nutrients from the water. At this point adding a nutrient solution to the water is necessary for the plant to continue to grow.
If you have any issues with hydroton floating then checkout this guide on how to make hydroton sink.
Items Needed To Start Seeds In A Hydroponic System
There are a few ways to start seeds in a hydroponic system. First, I will provide the bare minimum list and then the recommended items that can increase your germination rate.
Bare Minimum Seed Starting Items:
- Growing medium such as hydroton or coco coir
- Net cups
- Water
- Nutrients or nutrient solution
- Seeds
Recommended Seed Starting items:
Steps To Successfully Germinate Seeds Hydroponically
Seeds will germinate when they have water, light, oxygen, and heat. Starting seeds doesn’t need to be complicated in order to provide the four simple things they need.
Starting Seeds With Bare Minimum Materials
We will cover how to start seeds using just the five items on the bare minimum materials list.
To start seeds hydroponically using the bare minimum setup, you only need five items. A container, a net cup, hydroton, water and seeds.
Step 1: Fill A Small Container Full Of Water
First you need to fill a small container with regular tap water up to the net cup water line. So in my photo below, I filled the entire glass jar with water since the net cup is taller than my container.
Step 2: Fill A Net Cup With Hydroton
Next fill a net cup full of hydroton. Fill the net cup until the hydroton is level with the rim of the net cup.
If you have new hydroton then be sure to thoroughly rinse the clay pebbles before using them. It is also recommended to soak the hydroton for 6 to 24 hours before using them but this is not required.
Step 3: Place The Net Cup Into The Container Full Of Water
Now place the net cup full of hydroton into the container full of water. Make sure that the net cup’s rim is above the water level.
The goal is to have some of the hydroton partially stick out of the water.
Step 4: Drop Seeds Into The Net Cup With Hydroton
Finally drop your plant seeds into the net cup with hydroton. I recommended dropping at least 3 seeds into the cup so you have a higher chance of germination. I dropped 10 lettuce seeds into my net cup due to the seed’s tiny size.
Ideally you want to drop seeds onto the hydroton that is at the water’s edge. The seeds prefer to be moist and the hydroton will provide enough moisture for the seeds to germinate.
You do not want to drop seeds straight into the water since the chances of it germinating will be very low.
Once the seeds germinate, the plant’s roots will shoot down towards the water and will be able to get enough water through capillary action from the hydroton. Eventually you should see the plant’s roots extending out of the bottom of the net cup.
Step 5: Wait Three To Five Days For The Seeds To Sprout
After 3 to 5 days you should see healthy little sprouts from your seeds. Below you can see from the 10 lettuce seeds that I dropped that 6 plants sprouted.
Keep in mind, I accidentally dropped 1 in the water and 1 other seed stuck to the side of the net cup. So really I germinated 6 out of 8 seeds for a 75% germination rate which is pretty darn good.
So even with the bare minimum setup, I was able to get 6 healthy lettuce seedlings.
After about 7 to 10 days I will transplant these seedlings into larger hydroponic systems. This way the lettuce plants can grow until they’re ready for harvest in about 20 to 30 more days.
Starting Seeds With Additional Recommended Items
Adding the recommended items to the seed starting process provides a lot of benefits for increasing the seed germination rate. These items are helpful if there are a limited number of seeds or if the seeds are expensive.
Starter Plugs Or Rockwool
The first recommended item is starter plugs or rockwool. These are used to provide a home for the seeds to germinate and grow.
Rockwool and starter plugs or even coco coir are able to draw in enough moisture while provide enough oxygen for the seeds to start.
Seed germination rates should be closer to 90% when using starter plugs and can even be 100% if the seeds are fresh and healthy.
Grow Tray
Grow trays are another item that help increase the germination rate of seeds. These trays have a cover that help maintain a higher humidity level which seeds prefer.
Grow trays can be used to start seeds for hydroponic and soil gardening. By simply placing loose soil or a starter plug inside the slots you can easily germinate seeds.
Grow Tray Heating Pad
Growing tray heating pads help generate humidity for the growing tray. Seeds prefer to germinate in warm and humid environments which a heating pad helps create.
Air Pump And Air Stone
Air pumps and air stones are only needed to oxygenate water for hydroponics. These can help germinate seeds if seeds are being germinated directly in a hydroponic setup such as a container of water.
Air stones are not needed for starting seeds in a growing tray.
Air stones are not only helpful for starting seeds hydroponically but also most hydroponic systems. Plants prefer to have oxygenated water as water that does not have oxygen can drown the plant’s roots.
Conclusion
Starting seeds for hydroponics can be as simple as starting seeds in soil.
Seedlings purchased from the store or from seeds started in soil can be transplanted into a hydroponic system. However, starting seeds directly in a hydroponic system makes moving seedlings into a larger hydroponic system even easier.
Thankfully starting seeds hydroponically can be even easier than starting seeds in soil. By simply placing seeds into a net cup full of hydroton that sits in a container of water can successfully germinate seeds without any further maintenance.
By germinating your own seeds you can make sure to grow plants that you want at anytime of the year.
