Follow A-Grade Hydroponics - A-Grade Tutorials, Guides.. on Feedspot

Continue with Google
Continue with Facebook


Growing auto flowering varieties has become quite popular amongst the new generation of hobby growers due to their fast turnaround and compact size, making them ideal for many new and experienced growers.

Auto flowering varieties completely mature from seed to harvest in 8-12 weeks, which means they are not subject to photoperiodism.

Autos are Day-neutral plants which means they flower without regard to photoperiod.

Plants like Canna (short-day plants) flower without an inductive photoperiod, the induced photoperiod merely causes flowering to occur sooner, this is known as facultative photoperiodism.

Short-day plants vegetate best when the daylight hours are extended beyond normal. When the day hours are longer, the P-fr (Far-red) stores, cannot fully decay before the light comes back on, keeping the plant in a vegetative state.

Short-day plants exposed to a longer dark period (12+ hours) are able to fully decay their built-up stores of p-fr, which initiates phytochrome to trigger flowering.  

For some plants, the requirement for a dark period is absolute, they are classified as long-night plants and they will not flower until exposed to long nights, this is known as obligate photoperiodism.



  • Despite popular belief, you can start your seedling in a much smaller pot than the suggested final container.
  • Germinate the seed in preferred starter plug/cube. (See germination tutorial)
  • Once the seed has its first pair of serrated true leaves transplant the plug to a 100ml pot using coco: perlite mix (70:30)
  • The seedling will thrive in this pot over the next 7-14days
  • Once the seedling has developed a nice root ball we now transplant to the final pot very carefully (Always wear gloves)
  • Now the plant is in its final pot we must feed daily, obviously, we want a moist pot, not saturated, if it is saturated then only feed small amounts of food, and try to encourage consumption.


  • Week 1 - 2 Medium light exposure (18/6)
  • Week 3 – 10 High light exposure (16/8)
  • Week 10 – 12 Medium light exposure (12/12)


*Note: Germination (7-10 day’s) low light levels, ideally T5 lighting. (20/4)



Like any plant we are feeding, we don’t go straight to the max dose, rather a gradual build of nutrition, relative to the growth of the plant.

Over the entire grow most Auto’s will generally not consume an EC above 1.8, in fact an EC higher will create the exact opposite of the intended outcome.

Less is more with Auto’s, for example here is a chart that should help you understand the building blocks of an auto;

The food should be kept simple:


WEEK 1-4

EC 0.6-0.8 – pH: 5.8-6.0

WEEK 4-6

EC 0.8-1.2 – pH: 5.9-6.1

WEEK 8-9

EC 1.2-1.8 – pH: 5.9-6.2

WEEK 9-11

EC 0.8-1.0 – pH: 6.0-6.2


EC 0.0-0.3 – pH: 6.0


Selecting how many plants, really does determine the end result especially if weight is a concern. Growing regular photoperiod varieties in this space is vastly different in comparison, one plant will fill this space quite effectively whereas most Auto’s will not.

The numbers are always a preference, so always do what is comfortable for your current situation. Most would grow 4-6 in this space, be aware that lower numbers may not fill the space as effectively.

Happy growing, please share this tutorial around if you think it will help someone in this situation!

Read Full Article
  • Show original
  • .
  • Share
  • .
  • Favorite
  • .
  • Email
  • .
  • Add Tags 
Humidity 102: Vapor Pressure Deficit — VPD Chart - YouTube


To correctly calculate the VPD of your growing space you will need the following statistics:

  • Ambient environmental temperature
  • Relative humidity
  • Leaf surface temperature
  • Canopy level temperature


First, find your saturated vapour pressure (SVP) for a specific temperature.
























































































From the information above we can now compute saturation pressure.

Saturation pressure can be looked up using a Psychrometric Chart or calculating via the Arrhenius equation.

The reason growers would want this information, is because it is the measure of the drying power of the air. This directly impacts transpiration rates and water movement within the plant.

It also allows a grower to correctly calculate how much airflow is needed per environment and by maintaining stability with RH and temp an accurate SVP can be achieved.

As VPD is the saturated vapour pressure minus the actual vapour pressure (SVP - VPactual) and VPactual = (RH*SVP)/100

We may apply the formula:
VPD = (100 - RH / 100)) *SVP)

Alternatively, VPD = (1 - (RH/100)) *SVP)

(RH) is relative humidity and (SVP) is saturated vapour pressure

*For example, take 80% (RH) at 25 C. From the list above, SVP = 3167 Pa

100-RH = 20
 20/100 = 0.2
 0.2 * 3167 = 633.4 pascals (Pa)

Note: for convenience VPD may be given in kilopascals (kPa).
For this example, 0.6334 kPa.

Click here to View a extremely handy VPD Chart here - Source: http://www.just4growers.com



http://physics.holsoft.nl/physics/ocmain.htm, cronklab,


Read Full Article
  • Show original
  • .
  • Share
  • .
  • Favorite
  • .
  • Email
  • .
  • Add Tags 

When starting out a new gardening project it can take a few weeks to get everything right, some start of perfectly and others don’t so this tutorial is to help those that are struggling thus far.

Firstly, if you haven’t read the humidity (Link here) or temperature (Link here & here) blogs you should probably read them first as they will help develop a better understanding while reading this current explanation.


So, your seedling or juvenile plant has some upturned leaves, why is this?

In the presence of high temperature and low humidity without human interaction, plants will over transpire (bleed water) to try and level the saturation pressure within the environment.

When this happens, major changes take place not only in the environment but within the plant and the root zone.

Feeding a plant that doesn’t have the ideal conditions can cause a multitude of issues: 

  • Toxicity/deficiency
  • Soft plant tissue & weak stems
  • Metabolic shut down
  • Over worked stomata


These issues if not corrected will cause most plant varieties to die back, they may reshoot at the base of the stem as a last-ditch effort to stress response but in most cases its over as quick as it starts.


So, how can I fix my humidity issue, my temps are fine?

The quickest fix in this scenario is a humidifier, they will change a rooms humidity from 35% to 65% within 5 minutes of operating, once the humidity remains a stable 58-65% you will find the leaves will slowly uncurl and flatten out, the stress period the plant may go through could be up to a 2-week period as it is trying to recover, so be patient.

The team at A-Grade also advise that when feeding is to resume that you use 25-35% less nutrient solution than you were previously using to make sure we are not further compounding any current nutritional issues as a consequence of the initial problem.
Read Full Article
  • Show original
  • .
  • Share
  • .
  • Favorite
  • .
  • Email
  • .
  • Add Tags 

Hydroponic growing is lots of fun and very satisfying when things go well.

With that in mind a lot of new and experienced gardeners have started to ask the question, which is the most reliable and rewarding method of feeding plants?

I have purposely titled the topic RTW v Recirculating as these are the two most preferred methods of feeding indoors.


What is Run to Waste (RTW)? 

The run to waste application is whereby a brain tank or main reservoir is set with the corresponding week at max dose, statistically the pH and EC target values do not change, which means every feed dispensed from the reservoir is at max strength. The same applies for those in a smaller operation, the nutrients are usually added to fresh water daily at max strength according to the specific dosage for that grow week, and then fed to the plants daily.

The waste aspect of the RTW terminology indicates that we are feeding to run-off, approx. 10-20% of the pots holding capacity and then disposing of all of this solution, never again to be re-fed to the plants. By doing this we are also removing any built-up elements not used in the previous feed.

Image credit: MagicBeaver


What is a Recirculating system? 

The recirculating style of growing has become very popular and is a very efficient way of feeding plants and reducing outgoings, so it is a much more cost effective approach to growing. It does have its downsides though.

For a recirculating system to be truly on point the target EC and pH values should NOT change as the volume reduces, this is actually quite hard to achieve with very little experience and/or as a hobbyist. 

Once a recirculating system is set up, the main concern is the rise of pH in conjunction with the depletion of EC.

Using a bit of foresight, we can see that if the target EC and pH is changing then so is the absorption of specific elements, if the pH rises elements will not even be consumed. Growers who choose to “top” up their EC with food a few days in to a live system can run into a multitude of problems, usually minor deficiencies that can progress due to nutrient antagonism.

There are some really good systems that understand a low EC is needed within this setup so if you are thinking about one, maybe consult your local shop to see the systems they have as most of the branded versions and they are quite good.

Image credit: FloraMax

So, which system is best?

It is preference at the end of the day but for the grower focused on results and less problems, I would say RTW is the best feeding method for indoor growing as it allows the grower to have full control of what is being fed to the plant.

Recirculating systems are by far the most efficient systems in terms of water and nutrient consumption, but problems can arise when re-feeding the same water back to the plant that will not occur with RTW systems.

Both systems have their pros and cons and most growers will likely find use for both styles of hydroponic systems, dependant on the crop.

Much love, and keep growing!


Read Full Article
  • Show original
  • .
  • Share
  • .
  • Favorite
  • .
  • Email
  • .
  • Add Tags 

Spring has just kicked off and gardeners all around Australia are prepping their gardens or pots for the impending season.

Usually around this time a lot of our indoor gardeners try their hand at outdoor growing, some have lots of experience and need very little assistance. There are some new gardeners and seasoned indoor gardeners that experience some issues making the transition, so this FAQ is generally aimed at the latter group, however all gardeners should be able to draw some tips or inspiration from this post too.


(Q) Do I have to use Soil if I am growing outside?

(A) No, you can use any growing medium successfully the most commonly used in Australia for outdoor container growing is Coco Coir.


(Q) How often do I feed my plants Outdoors?

(A) Depending on which substrate/medium you choose to grow in, also depends on the feeding rate. For example; Coco growers would feed once or multiple times per day as would the perlite/vermiculite growers, those who opt for a soil, if the soil is “living” then watering once a day is enough with no further amendments needed, this is only short lived and eventually the user would have to amend organics relative the plant’s needs.


(Q) How long is an Outdoor season? 

(A) There are many theories on this and I do not claim mine to be the go-to method, however results do speak for themselves and with rarely a failure I think the advice is justified. Mid-Late October – April-June, the reasons as to why one would start around mid-October would solely rely on the weather pattern. Also around this time growers who follow the zodiac would plant/germinate on a waxing Gibbous moon and harvest on a waning moon (which aligns similarly with April-June  The reason for the 4-7 week difference is because of the genetics, some varieties flower and mature much earlier than others, in a nutshell though your Indy and hybrid varieties will finish much earlier than the majority of the satty dominant ones.


(Q) I’ve heard pests can be an issue?

(A) Of course, they live outside too. The smartest approach here is aiming for prevention rather than cure. When your plants are small, mist the every 3-5 days with pyrethrum and/or a neem based oil like Mite-rid or a more organic approach, diatomaceous earth as a soil treatment and it can also be made up into a soluble spray using de-mineralized water and a few drops of surfactant. By doing this, your plants will develop a resistant barrier and will barely be touched. Remember if the plant is healthy not much can affect its immune system, insects usually attack due to weakness, so just make them strong!


(Q) Best hydroponic nutrients for outdoor growing? 

(A) All of them! They all have the elements needed for premium plant growth and flowering, the most common chosen for outdoor currently is; Hy-Gen & Cyco Nutrients.


(Q) Toward the end of the season what’s the best tip?

(A) In general I would say always be prepared to have to do some work, more specifically when it starts to rain and your precious plants are going into flower, moisture is the enemy. So droplets of rain sitting in the center of flowers is not good, id advise getting some form of coverage pre-setup in case it does rain, this way you can cover a tarp or sheet over and prevent them getting drenched. Another alternate is put them in a shed or even indoors if you have to. Last but not least is just remember to feed everyday sometimes twice! If you have your heart set on a specific outcome, you must remember to feed

Read Full Article
  • Show original
  • .
  • Share
  • .
  • Favorite
  • .
  • Email
  • .
  • Add Tags 

The following article is a guest piece from HY-GEN (Hydroponic Generations)

When we think of marijuana, the illegal drug that is smoked often comes to mind. However, medical cannabis and industrial hemp are two types of this ordinarily prohibited substance that are no longer illegal in Australia.


What is the Law Surrounding Medical Cannabis in Australia?

From 2014-16 the laws around medical cannabis started to change, and in February 2016 an amendment to the Narcotic Drugs Act 1967 – allowing for license and permit-based cannabis cultivation in Australia – was passed. This change in legislation made the supply of medical cannabis in Australia legal, however, each state and territory would be able to decide individually whether the use of medical cannabis was allowed or not.

Victoria was the first state to make this change. In April 2016, Victoria passed the Access to Medical Cannabis Bill 2016, which provided guidelines for manufacturing, supplying and accessing medical cannabis products in Victoria.

In July of the same year, NSW obtained the first license from the Federal Government for legally growing cannabis for medical purposes. Then, in August 2016 changes in legislation allowed medical practitioners in NSW to request permission for prescribing approved cannabis-based products to patients.

By February 2017, additional laws were passed, as the Federal Government gave the green light for approved companies to legally import, store and sell the drug until domestic production could meet demand. However, the medication could only be prescribed to patients with painful and chronic conditions. At the same time, this law was passed, the first license for private cultivation in Australia was issued in Victoria.

Jump forward to January 2018, and Australia is now growing medical cannabis domestically and has just made the decision to start exporting cannabis-based medicines. The Federal Government has ambitions to be one of the world’s leading producers and exporters of the medically approved drug, creating a sound domestic and international supply of the medicine.

The regulations that currently prohibit the exportation of the drug are expected to change when Parliament resumes in February. These changes will allow for the exportation of cannabis-based treatments, such as oils, patches, sprays, lozenges and tablets that are manufactured to relieve the pain and symptoms of a number of medical conditions.


What is the Law Surrounding Industrial Hemp in Australia?

As of November 2017, the laws surrounding industrial hemp in Australia have also changed. Updates to the Food Standards Code now allow for the sale of low-psychoactive hemp seed as food. The term ‘industrial hemp’ has been devised to distinguish the ingredient from ‘medical marijuana’, however, like cannabis-based medicines; research has shown that these hemp seeds come with myriad health benefits, including being naturally high in good oils, amino acids, valuable minerals and vitamin E.

To be considered low-THC hemp, the seeds have to contain less than 0.5 per cent of the psychoactive ingredient, tetrahydrocannabinol. Industrial hemp naturally has low levels of THC, however, levels do need to be monitored regularly as they can fluctuate.


What Does This Have to do with Hydroponics?

Hydroponic growing methods have proved successful for medical cannabis and industrial hemp growers, and as the law continues to make these products more accessible, demand for effective growing methods will continue to grow.

Hydroponics is the most consistent, effective and efficient way to grow plants, cannabis included, allowing growers to have complete control of their delicate crops and focus on producing medical grade plants with precision and reliability.

With Canada just recently legalising and regulating cannabis, we're bound to see similar easing of laws in Australia in the near future and the possibility of a large number of hydroponic and horticulture careers opening up.

As passionate growers of all kinds of plants, the very idea that growing a particular species of plant is a crime, is ridiculous for so many reasons.

What are you thoughts on the laws surrounding medical cannabis in Australia? Are we moving in the right direction by allowing people access to the plant? or should we continue to maintain the status quo of prohibition?

Let us know your thoughts on this topic in the comment section below.



Read Full Article
  • Show original
  • .
  • Share
  • .
  • Favorite
  • .
  • Email
  • .
  • Add Tags 

Flushing is a technique used in between feeding weeks to ensure nutrition is available to the plant at all times, it is also used in the maturation (harvest) stage of a plants life. Flushing your plants before you harvest is crucial if you want your crop to be resinous, aromatic and full of flavour.

Flushing your pots or systems free of nutrients allows the plants to consume the remaining nutrients within itself, if all of the plants ‘veins or lines’ haven’t been effectively cleaned, this will result in an unhealthy plant and a much harsher crop that generally tastes like the nutrients you were plugging them with!

Some cleansing products are dedicated to this phase and specialised solutions actively seek out excess salts and convert them back into useable forms for the plant.


Timing is key with flushing

Experienced growers understand the benefits of flushing weekly, this will result in a super healthy plant always consuming fresh nutrients.

Plants that go through life not ever being flushed will go through a myriad of problems only confusing the grower.

At A-Grade Hydroponics we recommend gardeners to flush once weekly in hydroponics and coco based systems.

Think of an un-flushed plant as sitting in a bath that has not been changed for a few weeks, its technically bathing in its own waste!

If you are reading this tutorial because you’re near the end of your flowering phase then follow these steps to ensure you’re not flushing too early.

  • Pay attention to the overall form of the flower and fruit, usually with an 8-week strain, the flowers development starts to plateau around week 6 - 6.5
  • At this time, we massively reduce our nutrient solution concentration.
  • Usually before this transition most growers would have an EC between 1.6-2.4
  • Remove any old solutions and replace with plain water, correcting the pH to 6.0-6.2
  • Most tap water in Australia is between 0.0-0.1 EC
  • Ideal maturation is 0.1-0.3 EC



The key here is to flush the pots until the water is running freely out of the base of the pot, you would then allow the plant to naturally dry up the pot itself, then its rinse and repeat for approx. 7-14 days.



For systems where the roots are permanently sitting in nutrient solution, such as Deep Water Culture. Remove old nutrient solution from tub/reservoir and fill with plain water at pH 5.8-6.0, the plants would then sit in this water for around 7 days until harvest.

Alternatively, some growers prefer to scale down the nutrient solution strength over a two week period until the EC of their reservoirs reach around 0.5 for the final 3-5 days, simulating that of a downscaling coco flush.


A harvesting tip:

Harvest your plants before the lights are due to come on, this ensures there are no left-over nutrients being circulated through the veins of the plant, remember as soon as light touches them the capillary action re-commences.

Utilising this method will also ensure in maximum terpenoid profile, after a long day of light exposure the terpenoid hydrocarbons evaporate, by harvesting this way you will always have a super aromatic crop!


Read Full Article
  • Show original
  • .
  • Share
  • .
  • Favorite
  • .
  • Email
  • .
  • Add Tags 

Separate tags by commas
To access this feature, please upgrade your account.
Start your free month
Free Preview