Why Use a General Hydroponics Feeding Chart for Cannabis
Nutrients, on the surface, are easy enough to understand. Once you start finding a suitable one, that’s when it hits you – right on the head. Even if you were to limit your choices to only a few of the most recommended brands, each one of them presents you with plenty of products. As if the essential nutrients alone are not enough, there are the amendments and boosters that should further boost growth and bud development. Well, to not confuse you further, let’s stick to the basics – use the feeding schedule/chart provided by the manufacturer.
In this article, we are taking a look at the Flora series fertilizers manufactured by General Hydroponics (GH). At no time are we suggesting that this is the only brand you should be using because there are others – such as Advanced Nutrients and FoxFarm – that are just as good. Using GH as an example is to illustrate the use of a feeding chart, which we will get into in a while. In this article we will look at the General Hydroponics feed schedule for weed and how growers can follow it or even customize it to suit their needs.
Drain-to-Waste vs. Recirculating Watering System
There are several hydroponics growing systems – and deep-water culture (DWC) is the most widely used. It is simple, quite easy to set up, and perfectly capable of producing incredible results. Nonetheless, you could be using another system, and the feeding schedule would still be applicable. You do have to decide between the method of watering – drain-to-waste (DTW) or recirculating.
What Is a Drain-to-Waste Watering System?
In most cases, DTW systems use water and a pump to distribute the nutrient solution. After an irrigation cycle, the excess nutrient solution is no longer recirculated back to the tank. Either it is discarded, or some people find good use – such as irrigating trees, shrubs, and other plants outside of the hydroponics system.
Pros
Proponents of DTW prefer this hydro watering method because of these advantages.
1. Prevent Transmission of Diseases
Most people have only one hydroponics system in a grow room. After all, there is a limit to the number of plants a state legally allows. Some people, though, may have a more elaborate set up that includes two or more systems. In this case, DTW is preferable, as each hydro set up would be using a separate tank. Thus, there is less likelihood of spreading water-borne diseases through the nutrient solution.
2. Easier Pest Control
As an extension of the above DTW advantage, controlling pests is more manageable by maintaining individual tanks than sharing one across two or more hydroponics systems. It eliminates the dilemma of adding pest control chemicals to control an infestation in one without affecting the plants in other systems that have no infestation.
3. Minimize Salt Accumulation
DTW calls for draining the entire nutrient solution. As a result, there is less accumulation of salts. In other words, your plants are less likely to experience a nutrient lockout due to the absence of excessive residue build-ups.
4. Avoid Clogging
In a DTW system, there are practically no pipes and emitters. As a result, there is also less likelihood of clogging. It saves you the hassle and the headache of frequent maintenance.
Cons
As great as DTW seems, it is not a perfect system. Anyone who tells you otherwise is lying. Here are some of the things you should think about before deciding to use this method of watering.
1. Wasteful Water Consumption
Each time you flush the system – and you do this much more often than a recirculating system – you are consuming plenty of water. It goes against one of the perks of using hydro – water efficiency and conservation.
2. More Nutrients Used
No doubt, there are plenty of nutrients remaining in a solution. Hence, by flushing, you are also discarding plant-usable nutrients. As a result, this watering method is more costly as you would need to buy more nutrients.
What Is a Recirculating Watering System?
As the name implies, this watering system recirculates the nutrient solution back to the tank for reuse. Like DTW, it entails the use of water and a pump. Because of the way it works, some people have taken to calling it an active system.
Pros
Recirculating the nutrient solution has its advantages – some affecting the plants directly, while another indirectly.
1. Fewer Nutrient Consumption
Because the nutrient solution is not drained and probably discarded, you use fewer nutrients throughout the entire plant life cycle. Instead, the only time you add nutrients is to replenish those used by the plants, raising the ppm to the optimal range.
2. Saves Water
You can expect your monthly operating expenses to be less than a DTW system. Compared to soil mediums, for example, you probably use less than 80% of water. It is your way of helping in the conservation efforts of this valuable resource. As for large-scale commercial marijuana farming, the cost of savings is enormous.
3. Less Labor
For large-scale farming, imagine having to test the pH and ppm levels of separate tanks. Instead of having tens of hydro setups, each with an individual container, using a centralized reservoir means you only have to check a single tank instead of many.
Cons
Like DTW, recirculating systems also have its disadvantages.
1. Clogged Pipes
A recirculating system has a more complicated piping network than DTW. As a result, there is more likelihood of clogging due to a variety of reasons. Some of these include algae and bacterial biofilm growth, and the accumulation of dead plant matters.
2. Faster Transmission of Diseases
If some pathogens contaminate the nutrient reservoir, the spread of disease is not limited to a single hydro setup. It affects all the plants grown in hydro systems that are tapped into the contaminated tank. There is no way to isolate, unlike in a DTW system.
3. Limited Variety of Strains
Marijuana strains vary in their growth rate and nutritional requirements. Because of that, you cannot grow different strains with drastically varying needs. You are limited to growing varieties that have the same life cycle, pH, and ppm demands. For sure, you cannot mix Sativa and Indica plants.
How to Choose Between DTW and Recirculating Systems?
Let’s make this simple. As a home grower, you can only grow a limited number of plants at any given time. That means you only have one hydro system. You are better off using the drain-to-waste system. One of its perks, when you replace the solution, is flushing. Not only does it reset the medium by removing excess nutrients, but it also ensures that the plants receive the correct ratio across their growth stages. You are also eliminating pathogens that may cause root rot.
As for commercial or large-scale farming, the cost of labor, water, and nutrients can raise the prices of buds to prohibitive levels, making it difficult to compete in the market. In this case, a recirculating system is much more beneficial.
General Hydroponics Flora Series
Once again, a reminder. By featuring General Hydroponics, Homegrown Cannabis Co. is not saying that this is the go-to brand. However, it isone of the most reputable. Most of the information provided here may be specific to their products, but the principles also apply to other brands. We will particularly focus on the Flora Series by General Hydroponics for reference.
Why Are There Three Parts to the Flora Series and Their Purposes?
The needs of the plants vary across different growth stages. For simplicity, you could divide it into seedling, vegetative, and flowering stages. In the case of General Hydroponics (and other brands), they created base nutrients in three parts to address the varying needs.
The Flora series consists of three highly concentrated nutrients in liquid form:
- FloraGro. Its formulation addresses the needs of the root system as they develop during the vegetative stage.
- FloraMicro. This nutrient mix contains minerals needed to promote growth, especially when the plants start flowering.
- FloraBloom. This liquid nutrient addresses the needs of plants to develop buds fully.
These nutrients are not used individually. Instead, they are combined in varying concentrations and mixtures. At any given time throughout the life cycle, your plants are getting the precise nutrients they need to thrive.
What Feeding Schedule Should You Follow?
General Hydroponics recommends using the 1-2-3 ratio:
- Seeds, cuttings, and delicate seedlings. Use 1/4 tsp each of the three liquid nutrients per 1 gallon of water.
- During the vegetative stage. Use 3 tsp FloraGro to 2 tsp FloraMicro to 1 tsp FloraBloom per 1 gallon of water.
- During the late vegetative to pre-flowering stages. Use 2 tsp each of the three liquid nutrients per 1 gallon of water.
- From bloom initiation to ripening stages. Use 1 tsp FloraGro to 2 tsp FloraMicro to 3 tsp FloraBloom per 1 gallon of water.
Note: The above are general-purpose general recommendations.
You can follow General Hydroponics feeding chart for cannabis for their nutrients, other manufacturers will have their own. They are easy to follow and use. Do note that based on their recommendations, you may have to adjust accordingly, depending on the growth rate of the marijuana plants.
Notice, for instance, the feeding schedule of Flora series for DTW watering systems.
Here is the recommended feeding schedule for a recirculating water system:
Both of them have a life cycle of 12 weeks. Sativa strains, for example, likely need more than that. In that case, you would have to make adjustments based on the specific growth stage.
Can You Customize the Feeding Schedule?
Most definitely, you can modify or customize the feed chart provided by the manufacturer. For one, they are merely general recommendations and not specific to marijuana plants. Moreover, different species and strains have their particular nutritional requirements. Hence, by all means, you can make your own feeding schedule. Remember to keep a record – that will help you optimize the concentrations and mixtures in future projects.
For starters, you could start with this feeding schedule for marijuana in hydro.
Drain-to-Water Feed Chart
This is a custom feed chart for growing marijuana plants in a drain-to-waste watering system hydro setup.
Important notes:
- Do not premix the concentrated liquid nutrients before adding into water. Instead, each nutrient is added into water, beginning with FloraMicro.
- The nutrient solution should be enough to provide a 10-20% runoff, which should always be removed.
- Maintain 5.5-6.5 pH. Make adjustments only after having added all the nutrients into the solution.
- Provide plain water every other watering.
- Repeat week 3 to extend the vegetative period.
- Repeat week 8 to extend the flowering period.
- CaliMagic is highly recommended when growing in coco coir or using reverse osmosis water.
Stage | Phase | Week | FloraMicro | FloraGro | FloraBloom |
Vegetative | Before spout | 0 | – | – | – |
Seedling | 1 | 1/4 tsp | 1/8 tsp | 1/8 tsp | |
Vegetative | 2 | 1/2 tsp | 1/2 tsp | 1/8 tsp | |
Vegetative | 3 | 1/2 tsp | 1/2 tsp | 1/4 tsp | |
Flowering | Transition | 4 | 1/2 tsp | 1/2 tsp | 1/2 tsp |
Early Bloom | 5 | 1/2 tsp | 1/4 tsp | 1/2 tsp | |
Early Bloom | 6 | 1/2 tsp | 1/4 tsp | 1/2 tsp | |
Mid Bloom | 7 | 1/2 tsp | 1/8 tsp | 1/2 tsp | |
Mid Bloom | 8 | 1/2 tsp | 1/8 tsp | 1/2 tsp | |
Late Bloom | 9 | 1/2 tsp | – | 3/4 tsp | |
Late Bloom | 10 | 1/2 tsp | – | 3/4 tsp | |
Ripen | 11 | 1/4 tsp | – | 3/4 tsp | |
Flush | 12 | – | – | – | |
Flush | 13 | – | – | – |
Optional: CaliMagic is optional. Should you wish or decide to add, use 1 tsp before sprout up until week 2. Then, reduce to 1/2 tsp beginning week 3 up until week 11.
Recirculating Feed Chart
This is a custom feed chart for growing marijuana plants in a recirculating watering system hydro setup.
Important notes:
- Do not premix the concentrated liquid nutrients before adding into water. Instead, each nutrient is added into water, beginning with FloraMicro.
- Maintain 5.5-6.5 pH. Make adjustments only after having added all the nutrients into the solution.
- Change the reservoir every 7-10 days. Top off with plain water between changes.
- Repeat week 3 to extend the vegetative period.
- Repeat week 8 to extend the flowering period.
- CaliMagic is highly recommended when growing in coco coir or using reverse osmosis water.
Stage | Phase | Week | FloraMicro | FloraGro | FloraBloom |
Vegetative | Seedling | 1 | 1/4 tsp | 1/4 tsp | 1/4 tsp |
Vegetative | 2 | 1/2 tsp | 1/2 tsp | 1/2 tsp | |
Vegetative | 3 | 1/2 tsp | 1/2 tsp | 1/2 tsp | |
Flowering | Transition | 4 | 1 tsp | 1 tsp | 1 tsp |
Early Bloom | 5 | 1 tsp | 1 tsp | 1 tsp | |
Early Bloom | 6 | 1 tsp | 1/2 tsp | 1 tsp | |
Mid Bloom | 7 | 1 tsp | 1/2 tsp | 1-1/2 tsp | |
Mid Bloom | 8 | 1 tsp | 1/2 tsp | 1-1/2 tsp | |
Late Bloom | 9 | 1 tsp | – | 1-1/2 tsp | |
Late Bloom | 10 | 1/2 tsp | – | 1 tsp | |
Ripen | 11 | 1/2 tsp | – | 1 tsp | |
Flush | 12 | – | – | – | |
Flush | 13 | – | – | – |
Optional: CaliMagic is optional. Should you wish or decide to add, use 1 tsp from week 1 to 3. Then, reduce to 1/2 tsp beginning week 4 up until week 11.
Manufacture-provided or Customized Feeding Schedule Is Up to You
Manufacturers try to make the life of people easier by providing feed charts of their products. You probably have heard about this too – start with a conservative dose and slowly increase to avoid a nutrient burn. Do these companies try to make you use more than enough nutrients to boost sales? No, but the feeding schedule they provided is only general recommendations for plants – not marijuana.
Once you have decided on a specific watering system, remember to buy the appropriate liquid nutrients. The Flora series, for example, has one formulation for drain-to-waste and another for recirculating.
During application, whichever brand you buy, always read the documentation. It is then up to you to customize the feeding schedule as you see fit for your plants.
If you have further questions about hydroponics and more specifically how to feed hydroponic cannabis then sign up for the Homegrown Forum, a completely free resource for growers to chat and educate one another on all-things cannabis, there is even a specific hydroponics section!