When to Stop Fertilizing Your Cannabis Plants

It’s important to know when to stop fertilizing your cannabis plants. Over-fertilizing can lead to nutrient burn, which can damage your plants.

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The flowering stage

Your cannabis plants have now been growing vegetatively for several weeks, and you’re now ready to begin the flowering stage. This is the time when your plants will produce the buds that you’ll eventually harvest and smoke. But before you start the flowering stage, you need to make sure that your plants are healthy and have all the nutrients they need.

The final two weeks

The final two weeks before harvest are when you should stop fertilizing your cannabis plants. They don’t need any more nutrients and, in fact, too much fertilizer at this stage can actually damage them. Once your plants have entered the flowering stage, they’ll start to produce buds. The buds will continue to grow bigger and denser until harvest time.

During the final two weeks, you should also stop using any kind of plant Growth Regulators (PGRs). PGRs are chemicals that can help control the size and shape of your plants. But during the flowering stage, you want your plants to grow as big and dense as possible. So using PGRs during this time will just end up hurting your yields.

After you stop fertilizing and using PGRs, all you need to do is wait for harvest time. Your plants will take care of the rest!

The vegetative stage

The vegetative stage is when your cannabis plants are growing and developing their leaves and roots. During this stage, you will need to fertilize your plants with a nitrogen-rich fertilizer. Once your plants have reached 6-8 inches tall, you can begin to reduce the amount of fertilizer you use. When your plants are 12-18 inches tall, you can stop fertilizing altogether.

The first two weeks

For the first two weeks of a cannabis plant’s life, it is in the vegetative stage. During this time, the plant is growing rapidly and does not need any fertilizer. In fact, too much fertilizer can actually damage the plant. After the two-week mark, you can start to fertilize your plants if you want to, but it is not necessary. The vegetative stage will last until the plant starts to flower.

The seedling stage

The first week

After you have sprouted your cannabis seeds and placed them in soil, you will need to fertilize them. Fertilizing cannabis plants is different than other plants because cannabis has a higher nitrogen (N) requirement during its vegetative stage. The best way to provide your cannabis plants with nitrogen is through a fertilizer with a 21-30-21 NPK ratio. This means that the fertilizer contains 21% nitrogen, 30% phosphorus, and 21% potassium.

You will need to fertilize your cannabis plants every week during the vegetative stage. The first week after you have sprouted your seeds, you will only need to give them 1/4th of the recommended dose of fertilizer. For example, if the recommended dose is 1 teaspoon per gallon of water, you will only need 1/4 teaspoon per gallon of water during the first week.

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