Germinating seeds for hydroponics
All plants start from a single seed; it's from this seed we get our harvest. Although plants can also be started as clones or cuttings from existing plants, this page will focus on starting with seeds.
As you will find with most hydroponic grows things can be as complicated or simple as you choose; seed germination is no different. Seeds can be planted in soil as per directed on your seed package or seeds can be germinated without the use of soil entirely. Here we'll look at the different ways in which you can germinate your seeds.
If you choose to germinate your seeds hydroponically there is no soil and therefore many of the common diseases for seedlings are avoided in hydroponic culture. You reduce to risk of the seed rotting as well as other fungal issues that can occur in soil germination.
Have you ever grown in soil and noticed that some plants start better than others? Typically seedlings with a strong start are the plants that will perform the best in your garden. Hydroponic growing allows you to control a lot of the variables that aid in a strong start for your plants.
Growers who switch from soil germination to germinating seeds hydroponically often report a much higher rate of germination rate than what they are used to. Sometimes as much as a 15% increase in the germination rate.
The only ingredients a seed truly needs to germinate is water and a little warmth. This will take the seed from its dormant stage and begin to activate the germination process.
Hydroponic grow mediums such as rockwool, vermiculite, perlite and yes even paper towel can provide excellent moisture and drainage for the seed. These conditions are ideal as they provide water, oxygen at optimal portions for your seeds. Once germinated you seedlings can even be planted directly into soil.
Hydroponic Seed Germination
Walk into your local hydroponics store, or go online and you will often see green cubes in various sizes. The smaller 1" or 1.5" rockwool cubes are specially designed for germinating seeds. The cubes come in sheets of various quantities. You may be required to soak the rockwool cubes prior to inserting the seeds. Rockwool has a high PH of about 7.5-8 the ideal PH for most plants is around 5.5-6.5. So you might ask yourself "how to I correct the PH for rockwool?". The answer really isn't that hard. You will need to correct the water you're going to be soaking the cubes in. Fill a pail with some water next you will need to get the PH of that water using a PH tester. More than likely you'll have to lower the PH of the water (make it more acidic). You can use a product called PH down or us Lemon Juice. Whichever you use you will keep adding small quantities till you've lowered the PH of the water to around 5.5. Next, soak the cubes in the water for about an hour. After that you're cubes will have a stable PH and you're ready to plant!
Place a single seed placed inside the rockwool cube. If you're feeling frugal cut your cubes in half to make them last longer. Using rockwool is a tried and true method of starting seeds for many large hydroponic producers in the industry. And this is important where some a high germination rate is wanted when using expensive seeds Once the seeds sprout and become more established seedlings they can be placed into larger rockwool cubes or into different grow mediums. The consistent and convenient size allowed cubes to fit into grow trays until they are ready to be moved into larger systems. Keep the cubes moist and once you feel your seedling is ready for nutrients mix a very light fertilizer program to begin feeding.
Perlite, Vermiculite and Coco
Fill a tub or small grow pot with with perlite: a white porous growing material. Other materials can be used, such as coco fiber, vermiculite. However, perlite makes an excellent growing media for seedlings because it wicks water well, provides adequate air space and does not change the pH of the system. Seeds are planted in the perlite media exactly as they are planted in soil. Small seeds can be scattered over the surface or planted in rows and covered with a thin layer of media, just enough to keep them moist. The maximum depth for any seed is from two to three inches.
Many seeds have stored nutrients in their tissues and do not need any additional hydroponic nutrients until they are fully sprouted. Water the seeds like you would in soil, just enough to keep them moist. Once you see they've sprouted you can try a light nutrient solution to feed the seedling. Careful that you don't water too much or too vigorously as you might wash the seed to the bottom if the container. Perlite will wick moisture so you don't even have to water directly over the seed to avoid washing it away.