Starting your seeds hydroponically has many benefits, but many people are unsure how to go about it. Starting cannabis from seed is an affordable and fulfilling way to start growing. It all starts with germinating cannabis seeds, followed by creating the ideal warm, humid environment for seedling growth. Giving your seeds (and then the seedings) the best support from the very start, you'll set yourself up for success Hydroponics is an ideal method for germinating seeds! An alternative way of growing plants will be to grow plants hydroponically. Hydroponics is a more hygienic and efficient method compared to soil based growing. It also protects your…
Hydroponic Seed Starting 101: A Primer for Beginners
Starting your seeds hydroponically has many benefits, but many people are unsure how to go about it. Shannon McKee gives us a primer on the basics of starting your own seeds to expand on what you’re currently growing.
Many people skip starting their own seeds because of the time and effort to get them started, but there are some great reasons to start your own seeds hydroponically. It’s so much easier to just go to the store to pick up some seedlings to pop into your system and get growing, right? Well, store-bought seedlings do have some downsides that can be avoided if you start your own.
The first is that you’re limited to what you can grow in your system. You have to choose from the options available at the store. However, if you start your own seeds, you can grow anything. This means you can grow your favorite heirlooms or even rare plants that aren’t found at many nurseries.
Adding seeds to your hydroponic system means that they won’t go through any trauma or root damage from being transplanted into your system. This process may also introduce diseases or bugs into your hydroponic system from the store.
Also, you get the satisfaction of growing a plant from a tiny seed rather than just picking up a seedling. Plus, a packet of seeds can grow a number of plants for just a few bucks, whereas the cost of only one seedling can be the same amount.
Seeds are also more cost-effective than buying one or two seedlings in the long run, as you can save some for the following year. The germination rate can decrease over time, but often, you can still get quite a few to sprout over the years until you have to buy your next seed packet.
What You Need to Start Seeds in a Hydroponic System
The first time you start your own seeds for your hydroponic system may be a bit more expensive at the beginning because you need to buy more materials than in future years. Seeds need water, light, oxygen, and heat to grow. You really don’t need anything too special to grow your own seeds.
You can use a grow tray with a dome for your own miniature greenhouse to create an ideal environment. If you’ll be growing your seeds in an area that is cooler, you may want to invest in a heating mat that goes underneath the grow tray to keep it warm as this is a necessary condition for sprouting to occur. Light is good to have as well as this will help your seeds sprout.
Inside of your grow tray, it can be beneficial to use a pot that works for your seeds and their future as seedlings in your hydroponic set-up. You’ll want to use starter cubes, such as those made of stonewool (rockwool). The key here is to use something that can withstand being immersed in water without dissolving, as it could clog up your system after transplanting.
Step by Step Instructions for Sprouting Seeds in a Hydroponic System
- The first thing that you’ll want to do is to soak your starter cubes in clean water for about an hour. After they’ve been given a chance to soak, put a few seeds into the cube’s hole. You’ll want to add several just in case you have some seeds that don’t germinate. Once they sprout, you can thin out the weaker plants to allow the strongest to grow.
- Prepare your grow tray with about an inch of clean water or nutrient solution that is at half strength. Arrange the light source and heating mat as needed. You can keep the lid on to keep the heat and moisture in the tray.
- Put these planted cubes into the grow tray and add water or the half strength nutrient solution as the level goes down in the grow tray.
- After about four days, you’ll start to see some sprouts emerging.
Some people prefer to use a Ziploc bag, rather than a grow tray, when trying to get the seeds to germinate as it functions like a greenhouse. Seal the bag with a little bit of air and put it in a dark place for about four days to get the seeds sprouted. Then, you can put the starter cubes with sprouted seeds into the grow tray.
Step by Step Instructions on Transplanting
Keep your tiny seedlings growing strong with your hydroponic nutrient solution. Once they’ve gotten bigger, you don’t have to make the nutrient solution half strength.
You’ll start to see the seedlings’ roots coming out of the bottom of the cube, and this is the sign you’ve been waiting for, as it means you can start transplanting. This can take about two to four weeks depending on what plants you’re growing.
Clear up a spot in your hydroponic system’s growing media for the seedling – cube and all. Gently transfer the starter cube into your growing media, and cover it gently.
Give the root system a chance to naturally seek out the water and nutrients in your system by top watering it for a few days to give it a chance to grow the root system.
Voila! You grew your own seedlings into a strong plant for your hydroponic system. Depending on the type of plant, you’ll be able to get your first harvest about four to eight weeks from the time you transplanted your seedlings.
Cut out the dependency of only being able to grow the types of plants that are available as seedlings at your favorite gardening store. Take a little extra time to nurture your seeds so that they become strong seedlings ready to transplant into your system. You’ll be able to take pride in your efforts with how healthy your plants are and your overall system’s health.
Grow Guide: How to Start Cannabis from Seed
Starting cannabis from seed is an affordable and fulfilling way to start growing. It all starts with germinating cannabis seeds, followed by creating the ideal warm, humid environment for seedling growth.
Giving your seeds (and then the seedings) the best support from the very start, you’ll set yourself up for success come harvest. Here are the basics to growing cannabis from seeds.
Where to Find Cannabis Seeds
At this point, there are hundreds of different online options for sourcing cannabis seeds . If you are growing indoors, the world is your oyster, as many websites are willing to ship nationally (or even internationally). Plus, if you master the indoor environment, you can recreate perfect conditions for even the most demanding of strains.
For those growing outdoors, try to locate a local breeder who also cultivates outside. These cultivars will be adapted to your unique climate and will likely produce better results.
No idea where to start? Seed Finder is an excellent resource for sourcing specific genetics and breeders in your area. But this is just one place among many in today’s weed-friendly world.
How to Germinate Cannabis Seeds
What You’ll Need:
- Cannabis seeds
- Paper towel
- Plate or tray
- Ziplock bag
- Heating mat (optional)
The first step to growing cannabis from seed is learning how to germinate them. Place cannabis seeds on a sheet of paper towel, laid on top of a tray. Dampen the towel with water so it’s wet but not soaking.
Fold the towel in half to cover the seeds, and enclose it inside a Ziploc bag. Place the entire tray on a heating mat, the top of a fridge or other warm area of your house. Cannabis seeds germinate between 71 to 77°F (22–25°C).
Check back every day for signs of life. If your seeds are viable, they should sprout within a week. If you are still waiting for a few to emerge after a week, toss those and begin again. If no seeds have sprouted, your seeds are no longer viable.
Ed Rosenthal recommends soaking seeds for 12 hours before germination. His formula uses water, a cannabis rooting solution and hydrogen peroxide.
This solution is a good option for commercial and large scale growers, as it reduces the risk of fungal infection and encourages rapid sprouting. Compost tea is another excellent option for a natural alternative.
Ideal Conditions for Cannabis Seeds and Seedlings
What You’ll Need:
- Germinated Cannabis Seeds
- Potting Mix (or Root Riot Plant Cubes )
- Propagation Tray with Dome
Once germinated, you must carefully move these tiny seeds into the soil or soilless growing medium like Root Riot Plant Cubes. When you start cannabis from seed, the aim is a warm and relatively humid environment.
Starting Cannabis With Soil
If using soil, choose an organic potting mix suitable for seeds and starts. Water soil mixture before use, and fill potting containers that have a drainage hole. Avoid pellets that are commonly sold at garden centers, as they don’t retain moisture well, and it’s challenging for cannabis roots to break free of the netting.
Using a popsicle stick, tweezers or a toothpick, lower the germinated seed into a premade hole roughly two the three times the height of the seed. As you gently fill in the hole, be careful not to damage the sprout.
Starting Cannabis for Hydroponics
For hydroponics, you’ll want to use Rockwool cubes or Root Riot Plant Cubes. These come pre-cut into perfect starter plugs, often with a hole in the middle for the seed.
Before use, soak the cubes in water and rooting solution until they are wet but not dripping. Gently lower the germinated seed into the hole using a popsicle stick, tweezers or a toothpick. Be extremely careful not to damage the early sprout.
Whatever option you choose, keep the seedlings at a consistent temperature: 68 to 77°F (20 to 25°C). Depending on where you live, a heating mat may be necessary. Use a propagation tray with a clear dome to trap the humidity in, but open up once a day to encourage a bit of airflow.
Lighting Requirements for Cannabis Seedlings (& How to Eliminate Stretch)
Seedlings and starts require 16 hours of light a day and eight hours of dark. You can even bump this up to 24 hours a day, and the seedlings will continue to eat it up.
What kind of grow light do you need for this early stage of development? Not the same capacity you’ll need for veg and bloom. Higher wattage types of HID lights (Metal Halide and High-Pressure Sodium) are far too powerful for sensitive seedlings.
Most growers use a simple LED grow light or a CFL fixture. Ed Rosenthal recommends 40 to 60 watts per square foot.
While these may not be entirely enough for veg and bloom, they produce enough light for seedlings without the added heat. This means you can place the lights close to the tops of the seedlings.
Place lights as close as possible to the tops of the starts, without raising the temperature over 77°F. You want seedlings to get enough light without burning them.
The goal is to avoid early stretching in your small cannabis seedlings. Healthy seedlings are short and wide, not tall and skinny. Stretching is when the sprout reaches tall for the light without putting out leaves.
Typically, under outdoor conditions, plants remain short for the first few weeks as they focus energy on building structure and root development. Stretching inside demonstrates the seedling is not getting enough light. The light source is either not intense enough or too far away.
When to Transplant Cannabis Seedlings
The primary goal for starting cannabis seeds in small pots is to encourage healthy and strong root development. Once the seedling has three to four sets of leaves, begin checking root development. This will likely be three or more weeks after germination.
Another telltale sign it’s time to transplant is when you notice roots begin to creep out from the drainage holes. If working with Rockwool, a key indicator it’s time to transplant is when the roots begin to outgrow the cube. A plant’s growth trajectory slows down if it is root-bound. If the roots have consumed the available space, it’s time to move up a size.
Cannabis Seedlings From Germination to Transplanting
Starting cannabis from seed gives growers access to a much larger genetic pool than what you can find locally from a clone supplier. Plus, if you’ve got the time to invest, it’s a much more affordable way to grow cannabis. Finally, if you are already set up with a veg and bloom room, you have everything you need to get started from seed.
How to Germinate Seeds in Hydroponics
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Hydroponics is an ideal method for germinating seeds! An alternative way of growing plants will be to grow plants hydroponically. Hydroponics is a more hygienic and efficient method compared to soil based growing. It also protects your plants from root rot or insects. You can also control the whole system as everything is automated in this growing method.