A Simple Guide to Starting Seeds for Hydroponics

Ed Wike
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Step 1: Get Your Materials

You will need to purchase a tray, a grow tray lid or capsule, nutrient solution, seeds, growing medium, and something to cut the top capsule or lid with.

A standard 10-plant-tray is recommended, which can take two lid or capsule cuttings. If you choose to use the lid or capsule, then the tray is not necessary.

Seed Starting Materials List

  • Rockwool cubes for germinating seeds.
  • Penlight or household lighting.
  • Humidity dome.
  • Bouillon cubes.
  • Watering can.
  • Seed tray.
  • Heat mat.
  • Growing medium.

Step 2: Fill The Cloner With Water

The next thing you’ll need to do in order to get your seeds started is fill the root/clone cubes with water.

To do so, you will take your cloning unit with the net cups and fill each one up with water.

The water needs to be clean and sterile. You do not want your seeds or the clones to grow in dirty water.

Once your cubes are filled with water, they will need to be shaken thoroughly to get the water to the lower levels.

Once you’ve done this process, you’ll leave the cubes to sit overnight. The water should absorb through the top of the cubes and fill the little holes inside the cubes on the bottom.

While your cubes are soaking, fill up any reservoir of water that you’re going to use. The most common reservoirs are the top reservoir and the bottom reservoir. You will want to fill them up to a certain level.

On the top reservoir, you will need to fill it above the pump, but below the mouth that the pump blows the water out of.

Step 3: Set Up the Air Pump

The air pump is very easy to set up. Attach the tubing to the air pump outlet, plug in the air pump, and place it on the inside of the tub near the plants. You want to make sure to create enough aeration under the seeds and compost without “splashing” too much water out of the tub. This is determined by the length of the tubing and how much air you are able to push into the tub. A good rule of thumb is to make sure there is a slow bubbling noise coming from under the tub and the bubbles are about the size of a lentil or pencil eraser. If you have a lot of splash or it is getting the plants wet, you are not able to produce enough air to get the roots established and you will need to try a few different lengths of tubing before your plants get too large. Another thing that can cause splashing is the air pump being too far away from the tub. You need to make sure that there is no air getting into the pump other than through the tubing. This could occur if you are in the grow room and the tubing is dragging on the floor and sucking in air. This will create too much air and cause splashing. Try turning off the blower fan in the grow room at first to make sure there is no air getting in the pump.”

Step 4: Place Starter Plugs and Seeds

Add a scant amount of water to each of the cells in the tray to around ¼ inch depth. Keep the level just above the plug's small hole. The seeds should be placed carefully in the small hole with the tap root downward. The seedling's top shall be placed up. The tap root will then grow downward.

The next step, is to put the tray in a warm place for 4 to 7 days. If you can keep the soil moist during this time, it will be beneficial.

If the humidity in the sealed conditions is not high enough, you can spray the surface of the soil with water about every other day or so. This is not necessary, but it will help the seeds to germinate. Spraying should also be done every time you water the seeds and plants along with the rest of the tray.

After this period, the seedlings should have germinated. Begin to expose the seeds and the young plants to light. The tray will now be placed in a bright location.

After this stage, water should be supplied once a day. Within about 2 weeks, the little plants should have grown to about ¼ inch in size. At this time, it will be time to transplant to larger units prepared with the hydroponics nutrients.

As the young plants are slowly being exposed to more light, they may begin to elongate. This is normal growth.

Step 5: Maintenance

The most creative, informative part is behind you – at least for a while. Now’s the time to relax and watch your plants grow.

Maintenance for this phase is very easy. Your plants will need plenty of light. If you are using synthetic lighting, that means you should be turning it on for 12 to 16 hours throughout the day.

It’s also a good idea to check the temperature at least once a day, if not more. When temperatures get too high, you can use a fan to keep them cool. When they become too low, use a heater.

Water your plants daily, and flush out the system once a week to prevent salt buildup.

Maintain a pH of at least 5.5, and try to keep the temperature between 70 and 80 degrees Fahrenheit throughout the day. If you can keep it between 70 and 75 degrees, you haven’t peaked too soon and will have more for your plants to bask in throughout the year.

Video Guide

Part One: The Basic Setup

One of the great advantages of hydroponic gardening is that you don't need a garden to have a lovely display of flowers or a productive garden. To grow organic produce or flowers hydroponically, you can set up your system in a table in a room or simply on your kitchen counter. A hydroponic garden is essentially a self-contained ecosystem.

The first step to setting up your system is to choose your hydroponic nutrient solution. There are many nutrient packages available to help you set up your garden. If you plan to start with hydroponics but eventually expand into soil-based gardening, it is best to purchase a full hydroponic nutrient package so it is easier to create the two solutions.

If you want to get a jump on the growing season, you can buy seeds or small plants instead of seeds. However, if you plan to start your seeds indoors, you should make sure the seeds are specifically labeled for growing hydroponically. You don't want to mix the seeds with regular soil-based seeds because the germination period will be different.

Part Two: Making Sure Seeds Germinate

Seed germination is one of the most important parts of the growing process.

What germinated plants becomes your final harvest and is the basis for your profit.

Any problems with germination can cause you to lose plants, money and valuable time. The bottom line is that if you can’t germinate your seeds you’re probably not going to harvest much.

Sometimes it’s tough to create the exact conditions required for the seeds to germinate, especially with hydroponics. So, you need to understand what you can do to help your seeds grow effectively.

Having consistent temperature is the most important aspect of seed germination.

Your temperature needs to be between 68‖90 degrees F and a temperature fluctuation of 10 degrees can kill a seed. If you have a heat mat and a light source you should set them to a standard temperature.

The best way to set the right germination temperature is by recording the current temperature in the room every day for a week. Knowing how the temperature changes over a week will help you choose the right settings for your heat mat.

When you first start your seeds, it’s a good idea to check the temperature every day or two to ensure everything is going smoothly.

Part Three: pH Water and Add Nutrients

You can make your water by using a pool pH test kit. Often times, with a pH level of about 6-7, your water will be good for your plant.

An extension to this is to check the pH daily until you feel it is stable, and then check 2-3 times weekly. When testing with a pH level of less than 7, you will want to add nutrients to your water to slowly change your pH to 7 levels. To do this, take a sample of water to a pool store and ask them to test it if they don't come with a kit. When you buy your kit, you'll receive instructions on how to add the nutrients. You will either add it constantly to your water, or do so weekly. This is called "dosing" the nutrient water. The amount that you add depends on what is in your water and how much you are dosing it.

There are two types of fertilizer. The measured nutrients are the liquid. The other are the dry fertilizers, which you add into the water as well. For example, if you are adding liquid nutrients in your water, you will want to follow the instructions from that manufacturer. If you are using dry fertilizer, you will want to dissolve the powder in warm water, then use the measuring cup included that has a spout. Add the fertilizer to your water according to the packet instructions.