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We receive a lot of questions from growers and CANNAtalk readers through this website, requesting our help in resolving issues they are experiencing in growing their crops.
As always our R&D department is more than willing to answer them! Below you can read the Frequently Asked Questions, which gives you a lot of information about growing.

Do you still have a question after reading, go to the contact form and submit your question.

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1. What is a substrate?

A substrate is a medium in which roots of plants can grow and which enables the plant to stand up.

2. Why do I have to use a different nutrient for both the growing period and for the flowering period?

a. The plant needs different proportions of nutrient elements in these different stages of development.

b. The plants acidifies the root environment when it starts to flower. This means the root environment needs different elements.

The exception is CANNA COCO. Due to the fact that coco medium has different characteristics than other media, there is one unique formulation for the entire cycle

3. How do I know when to start giving my plant the flowering nutrient?

As soon as the first signs of flowers appear.

4. Why do nutrients have an A & B version?

A & B together contain all the nutritional elements a plant needs. They are separated into a bottle of A and one of B to make both solutions as concentrated as possible. A and B together are 1 nutrient, you can't use one without the other. Always use A and B in equal amounts.

5. Why are A & B not available in 1 bottle?

If A & B would be together in one bottle much more volume would be needed to dissolve the nutrients. Never mix concentrated A and B together since insoluble nutrients will be formed.

6. What is the biggest difference between chemical nutrients and ORGANIC nutrients?

The biggest difference is their origin, which is the reason why the organic nutrients can be used for organic growing.

  • Organic nutrients are released slowly.
  • Mineral fertilizers are available from the start.

7. I want to try CANNA products can you please send me some samples?

We do not have samples of our products. The smallest size of bottles we have is 0.25 liters. We don't deliver to private individuals. Please contact one of our dealers.

PH and EC

8. What is the importance of pH measuring?

pH has a great influence on the availability of the different nutrient elements. Therefore be sure the pH is always in the right range. The best availability range in the substrate is from 5.2- up to 6.2.

But CANNA recommends a different range for each type of substrate:

TERRA 5.8 – 6.2
COCO 5.5 – 6.2
Others 5.2 – 6.2

9. What is EC?

EC means electrical conductivity. EC is a number presenting the total of dissolved salts in the water. They include salts originating from the water and salts that the nutrients added.


10. On your website/label you advice to use PK 13/14 one week while a shop recommended me to use it more weeks?

We recommend to use PK 13/14 always for one week when you use CANNA nutrients. The CANNA base nutrients already contain sufficient P and K during the rest of the cycle. There is a certain period during the flowering stage though, when we can't increase the feed for the plant any more, so we adjust the PK-ratio by adding PK 13/14 for that one week.


11. What different kind of substrates are there to use for growing?

There are many different substrates and growing methods, which roughly can be classified into 4 groups. CANNA sells different nutrients specifically developed for these different substrates or methods. The four groups are CANNA TERRA (pre-fertilzed soil and soilless media), CANNA COCO (coco substrates) and for inert substrates CANNA SUBSTRA (run-to-waste) and CANNA AQUA (for recirculating systems).


12. I'm using a re-circulating system. Should I use SUBSTRA or AQUA?

Both nutrients are developed for inert media such as rockwool, clay pebbles and many others. CANNA specially developed CANNA AQUA to work in recirculating systems with these inert media. CANNA SUBSTRA should be used when using a run-to-waste system in inert media.