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Optimal Nutrient Absorption: When to Start Feeding Cannabis Plants

Hey growers! Let’s learn when to start feeding cannabis plants their first dose of nutrients.

Cannabis needs 4 things to grow well. Light, carbon dioxide, water, and nutrients. The leaves handle the first two, while the roots focus on getting water and nutrients.

When you first plant seedlings, they have enough stored energy to open their first set of leaves and and begin driving a tap root down through the soil. Marijuana seeds get energy by breaking down stored food in the seed’s endosperm.

At this stage, the seedlings have their own energy stash and don’t need extra nutrients from fertilizers. The baby leaves, take care of creating energy.

Once your seedlings use up all their energy, they’ll need nutrients from an outside source. That’s where you, the grower, step in and give the plant its first nutrient boost.

Now, let’s talk about when it’s the right time to start feeding your cannabis plants and how to give them their first dose of nutrients.

When to start feeding cannabis plants

Once your plants have grown the first 3-4 sets of leaves, it’s time to give them their first feeding of nutrients.
When you plant your germinating seed to a small pot, it usually takes about 1-2 weeks for your seedling to use up all the energy left in the seed and starter soil. Your plant roots are now taking nutrients from the soil and from any added fertilizer.

The “first seed leaves” might start to turn yellow around this time. This is also the time we like to transplant the plants to a larger pot. After the transplant, we will give them their first dose feeding. This will be the day one of the vegetative stage.

*If you’re starting your seeds in a soilless medium like rock wool cubes, you might want to feed them a very diluted amount of veg fertilizer like BiG Plant Science Grow. 1ml for every 2L is a good start.

If you’re using BiG Plant Science and growing in soil, the first feeding dose is 1ml of BiG Grow, 1ml of BiG Calcium Plus, and 0.5ml of BiG Stimulus for every 1 liter of water.

Make sure to give them enough water and nutrients so that there’s some runoff from the bottom of the planter. A good rule to follow is to aim for 10% runoff. So, let’s say you’re feeding your plant 2 liters of nutrient solution, there should be about 200ml of runoff.

Having runoff helps ensure that your soil is fully soaked. As your plants grow, they’ll drink up water and nutrients faster.

How to feed your plants nutrients

Mixing fertilizer with water and feeding your plants is a simple process with a product like BiG Plant Science. First, you need to decide how much water you need for your pots. 2 liter of water per plant in a 20 liter pot is a good place to start.

You want to give them just enough water that you get %10 runoff from the bottom of the planter after watering. This ensures that the soil is completely saturated and nutrients aren’t being wasted.

Let’s take a look at the BiG Plant Science feeding chart to find out how much nutrients we need to mix to feed our plants with their first nutrients.

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We have one plant in a 20 liter fabric pot filled with coco and we want to feed it with 2L of nutrient water. According to chart, at the first week, we need to add 2ml of BiG Grow, 2ml of BiG Calcium Plus, and 0.5ml of BiG Stimulus for every 1 liter of water.

Grab a jug and fill it with 2 liters of water.

-Add 2ml of BiG Grow, 2ml of BiG Calcium Plus, and 1ml of BiG Stimulus. Remember to shake the BiG bottles each time before using them.

  • Give the jug a good stir.
  • Now, it’s time to check the pH of your mix using a pH pen. For coco-grown cannabis, aim for a pH between 5.8 and 6.3. This helps make sure the plant can use the nutrients effectively.
  • If needed, use pH up or down products to adjust the pH. Natural stuff like citric acid (lowers pH) or sodium bicarbonate (raises pH) can also help.
  • Now you’re all set to feed your plant! Water around the base and work your way out. Don’t pour water in just one spot, or it might create a hole in the soil, leaving it unevenly wet.
  • Be careful not to get water on the leaves, especially when they’re young and delicate.

That’s it for your first feeding. Give it about 24 hours, and you’ll notice your plant growing more. It means the nutrients are doing their job!

Find out how much nutrients you need for your grow

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