Many people think that hydroponic systems don’t lend themselves to seed starting and that you have to grow all your seeds into seedlings in the more traditional dirt seed starter mix. This setup can be a real headache, because it means having to then transplant your seedlings (dirty roots and all) into your clean hydroponic system. Even if you buy seedlings or plants from your favorite gardening store, you'll still have to worry about bringing home pest-hitchhikers or less than stellar specimens. The good news is that you can start your seeds hydroponically and bypass these inconveniences altogether.
Things You’ll Need
Starting your seeds in a hydroponic system will cost you a bit upfront, but after you've made the initial investment, you’ll only ever need to buy seeds and replacement items.
Your shopping list should include things like net pots, starter plugs, tubing, airstone, an air pump, seeds, and special nutrients to jump-start growth. You may also want to invest in a hydroponic cloner, or build one yourself. If you’re looking to go really simple, a high-walled tray will do in a pinch to hold your water and net pots and promote good germination.
Setting Up Your System
After you’ve assembled the components, it’s time to start setting up your hydroponic seed-starting system. Begin by filling up the reservoir of the container you’ll be using for your net pots. The water level should rise to be just under the pots. If you'd like, you can use regular tap water at this point. You can also add your nutrient booster in at this time, but be sure to follow the instructions on the package when doing so. Usually, you’ll use less nutrient solution for your seeds and seedlings than you’d use for a larger setup with mature plants.
Next, you’ll want to add the air pump and airstone into the system. Some may choose to ignore these items, but they can really help with root growth and do a great job of keeping your seeds moist. If you’ve ever had an aquarium, there’s a good chance you’ve used something like this before. Connect the air pump to the airstone using a small amount of tubing.
Once your setup is complete, it’s time to work with the seeds. You’ll want to start by soaking the starter plugs in water. After they've absorbed enough to help with the germination of your seeds, you can place them into the net pots.
Add several seeds to each starter plug in your system. It’s not a good idea to only use one seed per pot, as there’s a good chance that they won’t all germinate. Putting two or three seeds into your plugs will decrease the chances of you having to replant later on. Once your seedlings start growing, however, you’ll need to thin them down to the strongest ones in the plugs. Replant any starter plugs that don’t germinate.
You'll find it helpful to put a clear cover on top of your system. This cover will help keep moisture in your system instead of allowing it to evaporate into the atmosphere, and it will also increase the system's internal temperature to help your seeds germinate and grow.
Maintaining Your System
If you don't maintain your system properly, all of the effort you’ve put into setting it up will only go to waste. The good news here is that the maintenance is relatively easy. You’ll want to keep the starter plugs moist but not overly-wet, as this could cause some issues with rot. A good way to accomplish this is by wetting them lightly with a spray bottle. This moisture helps the seeds sprout — a process that normally takes about three to five days depending on what varieties you’re growing.
After the seeds have sprouted and grown a bit, you'll want to trim back the extra seedlings you put in each plug. You should select the seedling that’s the strongest out of the ones that sprouted, and protect it while you snip the others. There’s nothing worse than accidentally cutting the seedling you were planning on keeping. When you're all finished, you might even use the snipped plants to add some sprouts to your salads, depending on what you’re growing. Broccoli, alfalfa, peas, and beans all make for tasty sprouts.
After your seedlings are strong enough for transplanting, you can start moving them to the bigger system. If your seedlings already have several sets of leaves on them, it’s probably time to transplant. Typically, you can move your net pots from the starter into your hydronic system without much fuss or muss. You can also transplant your hydroponically-grown seeds into traditional pots or your garden.
Growing your seeds hydroponically is much easier than most people believe. You'll never have to worry about contaminating your system with dirt or something home that’s hitchhiked its way in on your seedlings, like spider mites. Plus, you can grow just about any seed you desire in your hydroponic setup, as opposed to having to choose from the seedling varieties available at the local nursery. It’s a much better way to grow strong and healthy seedlings efficiently and with minimum effort.