If you’re growing plants you know the importance of using nutrients to achieve healthy plants and high yields. However, what’s the right way to use nutrients?
As with most items, there’s not one cookie-cutter answer. The type and amount of nutrients you should apply depends on the crop you’re growing, the age of the crop, your growing methods, and a number of other factors.
With that said, some basic knowledge will help you understand how to add nutrients in a way that results in high-quality crops. In this article, we’ll cover some common nutrients and what they do for plants. We’ll also answer some common questions regarding nutrient applications.
Why Do Plants Need Nutrients?
Just as with humans, plants need minerals to complete the processes they need to survive. While we can survive for a while on white bread, nutrient deficiencies will eventually become apparent. The same applies to plants. All plants need access to more than just water, sunlight, and air.
Some nutrients, such as nitrogen and magnesium, are required for basic plant growth. Other trace elements help plants respond to their environments and complete processes such as the development of flowers.
How Plants Use Nutrients
One way to get an idea of how you should fertilize your plants throughout their growth stages is to learn a bit more about how different nutrients are used. Below is an overview of the different processes nutrients perform within a plant. Understanding these jobs will help make sense of why each nutrient is necessary throughout the growth stages.
Plant Growth and Structure
Plants use both sulfur and nitrogen for structural purposes. These nutrients are part of the carbon compounds within a plant. Therefore, they help strengthen plants.
Nitrogen is required in high amounts for vegetative growth.
Structure and Energy Storage
Phosphorus, boron, and silicon are responsible for energy storage and transfer. They also add more structural strength to plants.
Potassium, calcium, magnesium, chlorine, and sodium are key to helping plants send signals. These signals help plants react to changing conditions such as changes in temperature or water availability. Having good levels of these nutrients ensures your plant is adaptable.
Finally, you have nutrients involved in reduction-oxidation, or redox, reactions. These include nickel, zinc, iron, molybdenum and copper. These are responsible for reduction reactions and oxidation reactions within a plant. In other words, they make it possible for photosynthesis to work properly and for the plant to get the energy it needs.
Feeding Hydroponic Plants
One of the most common methods of growing good bud is through a hydroponic approach. This method gives growers control over variables such as nutrient availability.
In a hydroponic system, nutrients must be administered with precision every day. Growers must watch how the plant responds to a nutrient level and adjust the dose accordingly until it’s perfect.
Feeding Soil Based Plants
If you’re feeding nutrients to plants in a soil-based system, you don’t have to apply as often. This is because the soil holds elements and slowly releases them over time.
The general rule-of-thumb is to provide nutrients once every other watering, but some growers wait for every third or fourth watering. Rather than guess, take a soil sample to determine the fertility present in your soil. Based on this measurement, determine the right concentration and frequency using a feed chart. Monitor and make careful adjustments over time.
Precise tracking and nutrient dose adjustments are both signs of a skilled grower. That’s what leads to the best crop production in the end.
Getting the Nutrient Ratio Right
One of the first challenges that new growers face when purchasing nutrients is deciding which product is best for their grow. There are a variety of organic and conventional products available. All the options can be overwhelming!
No matter what product you choose, you must change the nutrients you’re applying throughout your plant’s life. This is because a plant’s nutrient needs change throughout its life cycle.
In the early vegetative parts of the growth cycle, nitrogen is the most important. This is because nitrogen is key to boosting vegetative growth. A fertilizer with a high nitrogen, low phosphorus, and mild potassium usually performs best. The Grow product from Green House Feeding is a good choice since it has an NPK ratio of 4-1-2.
Later on, when plants start entering the flowering phase, nitrogen isn’t as important. At this point, the focus turns to phosphorus and potassium.
The length of the flowering stage also plays a role in the proper fertilizer. Plants with short flowering periods require a lot of potassium right away, so a product like Green House Feeding Short Flower is a good choice. For plants with a longer flowering period, choose a product with a more balanced amount of nitrogen and potassium. The Long Flower product provides this balance.
Once you have the right fertilizers, your work isn’t over. You still have to provide them to your plants in the proper dosage.
Feeding the Right Amount of Nutrients to Your Plants
Even when you have the perfect nutrient supply and you decide on the right ratio of nutrients to use in your plants, you still have to feed them to the plants in the right intervals. That means understanding basic feeding durations and knowing how to read the signs of either too many nutrients or too few.
It’s also helpful to understand mobile versus immobile nutrients. Mobile nutrients can move throughout the plant, so deficiency symptoms occur in older growth. Immobile nutrients cannot move, so deficiency symptoms occur in new growth.
Below are common symptoms of nutrient toxicity and deficiency.
Too Many Nutrients (Toxicity)
- Salty crust on soil
- Discolored or even rotting roots
- Lower leaves yellowing
- Browning leaf tips
Too Few Nutrients (Deficiency)
- Delayed plant maturity
- Less than typical root growth
- Leaves falling off plants early
- Long, weak stems
- Discolored yellow or purple leaves
When to Start Using Nutrients
First off, don’t wait to apply nutrients until you see signs of deficiencies. At this point, your plants are already suffering.
When to start using nutrients depends on the media your plants are growing in. However, you should generally start adding nutrition when your plants are in the seedling phase of growth.
How Old Should Seedlings Be Before Using Nutrients?
Seeds are remarkable forms of life. The endosperm of a seed provides nutrition to the germinating seed and later seedling. Therefore, plants don’t require additional nutrients during their early phases of growth.
Don’t apply nutrients before seedlings have their first true leaves. If you are growing in an inert media, such as perlite or coco coir, begin applying low amounts of nutrients when the seedlings have their second set of true leaves.
If you’re growing your seedlings in a rich potting mix, they might not need any additional nutrient applications. Make sure to know the composition of your potting mix, so you can apply what the plants need.
Start Low with Your Nutrient Dosing
Feeding nutrients to a plant is a delicate practice, rooted in science. While there are recommendations for the dose you should give your plant, it’s always best to start low and slowly increase.
Start off with a nutrient dose about as low as 75% to 85% of the recommended amount. Slowly increase that amount over time until your plants respond optimally. You might find that a lower dose works better for your plants, which is quite common. Either way, you will eventually find the perfect dose for your plants and you will avoid issues like nutrient lockout.
When to Use Bloom Nutrients
As mentioned above, plants require different nutrients during vegetative growth and flowering. When you switch your lights over to 12 hours on/12 hours off, make sure to switch to bloom products.
How Often to Add Nutes During Flowering
How often to apply nutrients depends on your exact plants and conditions. It also depends on the products you are using. Supply companies can help you figure out the best application schedules for your grow.
However, during the flowering phase, you should apply nutrients every 2-7 days. Once again, finding the proper nutrient applications will require careful observation and adjustments.
Use a Feed Chart
It’s difficult to know exactly how much of a particular nutrient your plant needs during each stage of growth. That’s why a feed chart is a useful tool.
Feed charts are customized for different strains. They give novice growers a good foundation of information to work from throughout the stages of plant growth. As the growers become more experienced, they can customize their chart for their specific climate conditions, strain variations, water quality, and other localized conditions.
Through careful testing and minor adjustments, you can take an already effective feed chart and convert it into the perfect feeding formula for your crops. You’ll be amazed at how you can improve bud yield and quality with a well-optimized feed chart.
Should I Use Nutrients Every Time I Water?
The short answer, no! By applying too many nutrients you can actually hurt your plants. Excessive nutrient applications can cause issues with salt buildups and nutrient toxicity.
Flush Your Plants
It’s especially important to water your plants with just water right before harvest. This water helps remove most of the nutrients from your plant’s system during the last stage of production.
This is known as flushing, and it results in the best quality final product. The time to begin flushing depends on your growing methods. For soil-grown plants, start using plain water two weeks before harvest. For hydroponically-grown plants, you only need to flush a few days before harvest.
Aim for the Proper Nutrients
It’s nearly impossible to master the perfect nutrient concentration for your plants as a first-time grower. However, you can get close by selecting the proper fertilizer mixes, following a feed chart, and watching how your plants respond to your actions. By making careful adjustments, you can improve your results over time and become a better grower.