Cannabis seedlings are like children.
They grow faster and healthier when you nurture them through a steady and sustained program of lighting, feeding and watering…
And it requires both care and precision to provide them with an optimal environment to thrive.
In this article we’ll share some top tips for seeding cannabis, as well as how to avoid the most common mistakes cultivators make so you can position your plants for maximum development later on in life.
First things first, let’s discuss…
The Optimal Lighting Conditions For Sprouting Cannabis Seeds
Once you’ve germinated your cannabis seeds, it’s time to gently coax their growth for a productive crop cycle.
The first mistake to avoid at all costs?
Placing your seedlings beneath intense light too soon.
If you’re growing outdoors, you’ll quickly discover that direct sun is far too extreme, especially if you’re living in high-UV areas.
If your shrinking leaves turn downward, it’s a telltale sign that your seedlings are being exposed to too much light.
Instead, when sprouting cannabis seeds outdoors, provide them with mixed shade for the first 2-3 weeks of their lives.
And if you’re growing indoors, your seedlings aren’t quite ready for high-intensity lighting.
That’s why most growers use fluorescent grow lights or low-power LED grow lights for the first three weeks of the vegetative phase (if not longer) before switching their plants to either high-intensity discharge (HID) or full-power LED lights.
Next, let’s take a closer look at…
The Best Nutrient Regimen for Growing Cannabis Seeds
When learning how to grow a cannabis seed, some cultivators make the mistake of feeding their seedlings too early, too heavily, or both.
When a seedling only has a few sets of true leaves (e.g. those with serrated edges), its root development is minimal and unable to uptake large amounts of nutrients.
Make no mistake, besides over-watering, over-fertilizing is a leading cause of seedling failure.
And keep in mind that your growing medium matters, too.
It makes a big difference if you’re growing in inert media such as rockwool, in soilless mix or coco coir, in pure hydroponics such as deep water culture, or in soil.
If you’re growing in inert media or pure hydroponics, you’ll need to provide your seedlings with nutrients a day or two after they produce their first set of true leaves.
Feed them conservatively — even half strength it too much as their stage of development. For example, when using pH Perfect® Connoisseur® Grow, only use 10-15 percent of the full-strength dose.
If you intend to grow cannabis seedlings in soil, ask the soil manufacturer ahead of time if the soil you want to use is meant for seedlings.
Some manufacturers load their soil with too many nutrients, especially nitrogen. While this is a good growing condition for transplanted plants, it’s too nutrient-rich for seedlings.
With seedlings, less is more.
Your plants can sometimes recover if you underfeed them. But if you give them too high a nutrient dose, you risk burning their delicate young roots — and your cannabis seedlings will likely never recover.
How to Encourage Root Growth
Root growth is essential for sprouting cannabis seeds. The stronger their foundation, the more vigorous their development will be in both the vegetative and flowering stages.
To build a robust root system, consider using…
- A B-Vitamin Complex, such as that found in Advanced Nutrients’ B-52®. With both a B-vitamin complex, kelp, and essential nutrients, B-52 is a powerful product for protecting your plants from abiotic stresses. And its humic acid stimulates microbial activity in your root zone, encouraging increased nutrient uptake to help your young plants thrive.
Use 1–2 ml of B-52 per gallon of water, and refrain from using it every watering cycle. It contains small amounts of nitrogen, phosphorus and potassium, which are added benefits for early growth.
- Beneficial bacteria and fungi. In nature, plant roots evolved with microbes that protect, stimulate and enhance roots. You can add those microbes into your root zone using hydroponics products made especially for cannabis. Such products include Advanced Nutrients’ Voodoo Juice®, Piranha®, and Tarantula®.
For a more cost-effective route, try the Voodoo Juice® Plus — a new innovation that provides all the benefits of these three liquid products in one convenient quick-dissolving tablet.
Use 1–2 ml per gallon of water for each of these products, starting two days after your seedlings produce their first set of true leaves. As your seedlings gain leaves and height, begin to follow the dosing instructions on the label.
The best way to ensure an accurate feeding schedule?
Use the BudLabs Nutrient Calculator. With easy no-math mixing, BudLabs can help you determine which nutrients to use for your cannabis seedlings — and the exact ratios to prevent overfeeding.
And finally, take a look at…
More Top Tips For Seeding Cannabis
Now that you know the optimal lighting conditions and nutrient regimen for your seedlings, you’re well on your way to setting them up for strong and sturdy development.
Here are three more tips to optimize their ability to thrive…
- Place a small oscillating fan so it blows the seedlings gently, from side to side. This will help to strengthen their stalks, so the plants grow to be sturdier later on.
- Use reverse osmosis water, rainwater, or tested and clean well water. Cannabis seedlings are very sensitive to chlorine, chloramine, pollution, pesticides, and other contaminants found in most municipal water supplies.
- Give seedlings an environment with 57–67 percent relative humidity for the first 1–3 weeks of their lives. It’s not uncommon for grow ops to have indoor air so dry that their seedlings die.
Seedlings don’t usually need a humidity dome like young clones do, but they do need the aforementioned humidity range until they’ve developed strong enough root systems to draw moisture from below.
Now you know exactly how to grow a cannabis seed and position your plants for maximum development. For more tips on getting the most from every stage of your crop cycle, subscribe to the Advanced Nutrients newsletter.