I’ve tried several different methods of germinating seeds for my hydroponic gardens. My preferred method is using Rapid Rooter plugs made by General Hydroponics. They are easy to use, have a great germination success rate, and can be used in all of my different types of hydroponic systems. Here’s what you need to know about using Rapid Rooter for seed germination.
What Are Rapid Rooter Plugs Made Of?
Rapid Rooter plugs are made from composted materials. I’ve used some derived from peat moss and others from tree bark.
Rapid Rooter plugs are formed in a way that creates an optimal air-to-water ratio which promotes excellent root growth. I’ve found Rapid Rooter starter plugs way easier to use compared to other seed starting methods, such as using rockwool.
Supplies Needed To Germinate Seeds Using Rapid Rooter |
||
|---|---|---|
| Rapid Rooter Plugs & Tray– The kit comes with 50 Rapid Rooter starter plugs and a tray that holds water to keep plugs moist. |   |
View Product |
| Heat mat– Many seeds have higher germination rates when the temperature is in the 70 to 80 degree range. |  |
View Product |
Also Needed: Seeds, a bowl of water |
||
How Use Rapid Rooter To Germinate Seeds For Your Hydroponic Garden
The first thing to do is soak the Rapid Rooter plugs in distilled water. Some people soak them up to 24 hours; I typically soak them for only a few hours and have had no issues. After soaking, place the plugs into the grow tray.
Plant Your Seeds
Place a few seeds in the center hole of each Rapid Rooter plug. Planting more than 1 seed increases the chances of successful germination for each plug.
Tip* Tear a little piece off the bottom of the Rapid Rooter plug and place it over the hole where you placed your seeds. This will keep the seed completely dark, which is necessary for germination.
Some seeds may germinate before others and they will be able to push off the pieces of the cube as the seedling emerges, exposing itself to light. That way other seeds that are still in the process of germinating will still be in the dark.
Fill With Water And Cover Grow Tray
Next, fill the grow tray with about a quarter-inch of water. There are holes at the bottom of the tray where the plugs go, allowing the plugs to wick up water and stay moist. Cover the tray with a dome to keep in moisture and warmth. If you don’t have a dome, you can cover the tray with saran wrap.
Place the grow tray under a low-intensity light for seedlings and keep the Rapid Rooter plugs moist by adding water to the tray as needed.
Seeds have a better germination rate when provided with some extra heat. I recommend placing a seedling heat mat underneath the tray to maintain a warmer temperature.
How To Know When Seedlings Are Ready To Be Transplanted
As the seedlings grow, they can be put under more intense light geared toward vegetative growth. As the seedlings develop, you’ll start to see the roots start to grow out of the rapid rooter.
When you see a good amount of the root system coming through the Rapid Rooter it’s time to transplant.
Transplanting Plants From The Rapid Rooter Tray Into Your Hydroponic System
Rapid rooter plugs are very versatile and can be transplanted in any hydroponic grow medium as well as dirt. As soon as you get them transplanted over into the hydroponic system, you can introduce them to a low-level dose of nutrient solution.
 | My Top Pick | 11,700+ Reviews |
Conclusion
Rapid rooter starter plugs are my preferred method when I start seeds for my hydroponic gardens. Using these starter plugs makes the process so much easier compared to other germination methods.
Plugs promote a healthy root system in seedlings to start your garden off on the right foot and replacement rapid rooter plugs are affordable.
June 4, 2017 at 11:57 pm
Do the seeds in the rapid rooter get light right away? 24 hours like veg stage?
June 8, 2017 at 6:52 pm
Chase,
Thanks for the question! I would recommend waiting for the seeds to sprout above the top of the rapid rooter before placing them under light.
November 28, 2017 at 2:18 am
DO you need to seal the hole above the seed or is it okay to leave it open?
November 29, 2017 at 1:42 am
Good question. Covering the hole may be necessary if you can not germinate seeds in dark place. It’s especially helpful when germinating tricky seeds where some may sprout before others. That way you can have the light on for those that are sprouting while still allowing the other seeds time to sprout.
March 18, 2018 at 12:54 am
Covering hole is fine from seed. Don’t push torn piece of cube into hole in cube where seed is. Just take large enough piece to cover hole to stop light and remove to check germination.
If cloning cuttings, I always push small piece of cube down middle to support and keep light out
April 14, 2018 at 5:47 am
hi, can I use rapid rooter to germinate my seeds, then transplant into potting soil for?
July 8, 2018 at 12:04 am
Absolutely, plants germinated in rapid rooter can be transplanted into dirt.
October 25, 2018 at 7:48 pm
Do you have to wait for the seed to start sprouting before putting in rapid rooter?
October 25, 2018 at 10:04 pm
It’s not necessary to start the seeds before placing them in the plug.
January 2, 2019 at 9:47 pm
Will the seedling drown if tap root grows down into the water?
January 4, 2019 at 11:42 pm
Rapid rooter plugs provide a good air to water ratio for the plant’s root system, so the seedling won’t drown if the tap root goes down into the water.
January 5, 2019 at 8:54 am
So if i put about a quarter inch of water in the tray to wick up into the rapid rooter it wont get to soggy? And drown the seedling? At what point should i remove the water? Or should i keep water in the tray until ready tp transplant?
January 8, 2019 at 5:58 pm
You’re correct on the amount of water to add and it won’t get too soggy. The rapid rooter plugs will wick up water from the bottom and need to stay moist until seedlings are ready for transplanting.
October 2, 2019 at 4:01 pm
Hi, I am a new grower, and just purchased an AeroGarden Farm XL, which will be arriving tomorrow. I suppose by this time tomorrow, I will have gotten an answer elsewhere, but I need to ask if this step is necessary for the AeroGarden, or can I just germinate the seeds straight from there?
October 2, 2019 at 9:10 pm
Hey Dave! First let me say I’m jealous. The Aerogarden Farm is super cool! You should share some pictures in the forum or on the facebook page once you get your garden going. I’d love to see it!
To answer your question, the Aero gardens use seed pods. Just purchase what seed pods you like, pop them in and you’re ready to go
October 19, 2019 at 6:35 am
Have rapid rooter plugs leftover from a previous grow about one year ago. Despite being in a sealed plastic bag, a small amount of white mildew has formed on the exterior of the plugs. Can these plugs be used, cleaned, or thrown out?
October 19, 2019 at 2:37 pm
Hey Harold! I imagine some airborne spores made it into the bag while it was open at some point. I would recommend throwing them out and starting from know. Seeds and seedlings are already susceptible to damping off, so better safe than sorry.
May 3, 2020 at 11:46 am
I just received my Rapid Rooters. My problem is I do not have a grow tray, what can I use instead? I plan on putting them in my tent as soon as I get them planted and should I use my light?
May 12, 2020 at 6:11 pm
If you have a small tupperware you can place them together so they don’t fall over. Make sure to keep the bottom filled with water.
July 10, 2020 at 10:28 am
How long can you leave your plants in the seed starters before you have to put them In pots?
August 1, 2020 at 11:15 am
Hey Krista! It really depends on your plants, there’s not really a set amount of time. As long as they are getting nutrients they should be ok, the first issue that would arise is spacing.
July 24, 2020 at 12:42 pm
I got RootTech because I’m hoping for better results my second round, w/o buying more autos.
I used these Rapid Rooter plugs the first round, any they were awesomely easy to use. I’ve more.
I found this site today when trying to learn how to use RootTech, and then read this. Could I expect good results using the combo of RootTech + RapidRooter?
August 1, 2020 at 11:22 am
Hey Neil! I’ve had really good results using rootech and rapid rooter.
December 1, 2020 at 11:16 pm
Can you use Quick Rooter to grow microgreens? How would the method change?
December 2, 2020 at 10:12 pm
Hey Michael!
First off, great name! I wouldn’t recommend using rapid rooter for growing microgreens. I don’t have a specific article yet but I would recommend growing fodder similar to growing hydroponic fodder. Not with a grow medium but sprouting the seeds and watering the root mat.
August 20, 2023 at 9:48 pm
Hi Michael,
Thanks so much for all of your articles on getting started with hydroponics – they´re giving me the confidence I need to get started.
If I start seeding in rapid rooter plugs, what´s the process at transplant time? Do I need to remove the soil from the root plugs before transplanting into a medium such as the hydroton clay pellets? Thanks.
October 10, 2023 at 10:59 am
Hey Steve! When transplanting seedlings in rapid rooter you can plant transplant them straight into your hydroponic system. You don’t need to remove any of the rapid rooter material and can plant them directly into your hydroponic clay pebbles.