How & When to use Cal-Mag

How and When to Use Cal-mag for Growing Cannabis

Growing cannabis is a lot of fun until your plants start dying without any rhyme or reason.
Well, there certainly is a reason, but you may not see it first. Moreover, this can be very frustrating, especially if you’ve cared for the plants like they are your own children. Among the many problems facing plants, cannabis nutrient deficiencies are the most common and can end up causing nutrient lockout.

What is Cal-mag and how can we use it in cannabis growth and when is the Right time to use it?”
Some of you may be thinking about Cal-mag and why should you need to use it for cannabis!
Knowing that your plant has a nutrient deficiency is essential for maintaining a healthy crop because cannabis plants need nutrients to develop the branches, leaves and further along into their growth cycle, the buds.

A nutrient deficiency occurs when your plants don’t get enough food, become stressed and can be more susceptible to bugs, mold, and diseases which can reduce the yields and ultimately kill your plants. These nutrient deficiencies often present in the leaves, such as yellowing, burnt tips, and in more serious cases, crispy and burnt leaves.

it’s important to know that a nutrient deficiency is not only caused by underfeeding but also due to improper pH levels and should not be confused with nutrient toxicity, which is caused by excessive feeding.

Cal-mag is nothing more than a supplement of Calcium and magnesium and other nutrients, cal-mag deficiency often happen together in plants. This is why most growers deal with cal mag deficiency at some point. The easiest way to deal with cal mag deficiency is to add good quality composite to the soil.

You can add garden lime, crushed eggshells, dolomite, and even fish meal to enhance the quality of your soil. And of course you can Use a Cal-Mag Supplement directly.
So you can mix Cal-mag with your normal nutrients solution that you can store in gallon of water.

The reason of using cal-mag is to fulfill the requirement of minerals to plant. If we talk about the dosage of Cal-Mag then the exact dosage would be 3-5 ml per gallon of water, this 5ml will be equal to one teaspoon so for 5 gallons it will be 20-25ml of Cal-Mag.

5ml will be the initial dosage amount for soil if you have existing calcium and magnesium deficiency in your plants. But if you want to use it as a preventive measure then you need to start with 1-1.5ml per gallon.

If using a soilless medium such as coco coir, then it’s a good idea to load up on the Cal-Mag prior to transplanting your established clone or seed. Start with 5 mL/gallon for the first few watering’s, then reverse back to 1-1.5 mL/gallon thereafter.
But when should you use cal-mag?

If you are experiencing calcium magnesium deficiencies then we recommend not waiting, applying 1 or 2ml of cal-mag per gallon of water and pouring straight to your plants. the ideal time of using cal-mag is in day time or after the lights turn on, Because during the day the movement of water is quicker than at night.

The best way to resolve nutrient issues with cannabis is to catch them early. But it’s even better to prevent likely issues outright, which is why you should use a light dose of Cal-Mag throughout your grows

So, in summary the starting dosage of cal-mag should be 1-3 ml/gallon as a preventive measure. And for most growers the ideal time of watering is just before the rising of sun. Because plant will stay in a healthier environment all day long.

Let us know how you use cal-mag in the comment section below, and of course if you enjoyed this video to like and subscribe so you too can become a cannabis expert!

50 Comments

  1. @TherealBDL on December 8, 2024 at 12:48 am

    Espom salt (magnesium)and egg shells+vinegar (calcium). Never needed to buy calmag.

    50ml calcium / 1 TSP salt / 10L of water. Water every 5-7 days or when they need it

  2. @jamiestewart7327 on December 8, 2024 at 12:48 am

    If you want someone to narrate that doesn’t sound like posh douche, let me know 👍🏽

  3. @greenthumb1897 on December 8, 2024 at 12:48 am

    So if i use eggshells on soil when is the right time to put it into my soil? Like week 3 of flower?

  4. @charlesweber4925 on December 8, 2024 at 12:52 am

    It would be fun if this were all in, ooh, say metric. In some perverted parts of the world, there is the U.S. gallon, the Imperial gallon, and this new fangled Metric scale. Perhaps not at this level, but with some mixtures, expressing them as a ratio can be a bit more universal. This comment is just to keep you guys on your toes. The price being charged for the information however, can not be beat!

  5. @bertolf162 on December 8, 2024 at 12:54 am

    Die Dosierungsempfehlung ist total sinnlos… entscheidend sind die Wasserwerte und das Medium das man nutzt. Und wenn man nicht gerade die beschissene BioBizz Erde nutzt oder Magnesium-freies Wasser gießt, wird man nie Probleme damit bekommen.

    Und selbst wenn, dann kauft man sich Bittersalz ausm Baumarkt, das besteht zu 90% aus Magnesium und kostet 4 euro im 20l Sack…. oder man hat halt gar keine Ahnung und kauft sich CalMag…..

  6. @tjizzle8155 on December 8, 2024 at 12:55 am

    Anyone know the best way to use ammonium nitrate and calcium nitrate …put in water let dissolve then pour around plant or place in soil pour water over soil….and what stages…thanks

  7. @German_Growdiary on December 8, 2024 at 12:55 am

    I use calmag since begining. 0,3 ml per 1 liter water and grow with soil

  8. @mgray612 on December 8, 2024 at 12:55 am

    this is one of the worst videos ever produced sheesh!

  9. @beimircc6434 on December 8, 2024 at 12:57 am

    Wtf is a gallon..😂

  10. @nebulaM16 on December 8, 2024 at 12:58 am

    I know it’s two years old but I have to say…, it’s total BS….
    First of all and most important is what kind of water you use, is it tap water or RO water, now and only now you can start to determine the dosage/amount, tap water has to be measured and analyzed what and how much is in it already, for RO water with a 0.0 EC it’s 2ml of CAL/MAG per Liter and you also have to add micro elements….

  11. @Danielfiscus on December 8, 2024 at 12:59 am

    U did not help at all thanks for wasting my time

  12. @Jumbo344 on December 8, 2024 at 12:59 am

    I’m using a cheap cal-mag and it calls for 10ml a litre and I been giving it 20 every fed😂 haven’t had any problems as of YET

  13. @dennisfolz352 on December 8, 2024 at 1:01 am

    My tap water has perfect calcium and magnesium

  14. @ChrisShuff on December 8, 2024 at 1:01 am

    I use an Ro system for my water because my tap is hard, I add 5 mL of Cal mag to my nutrients with every feeding, I even added to the days in between feeds when I water.

  15. @Anonomush_oranges on December 8, 2024 at 1:02 am

    It also prevents blossom end rot in tomatoes.

  16. @paulwhite9275 on December 8, 2024 at 1:02 am

    I use a light dose of cal mag every feeding and never have issues. Green big and healthy

  17. @scottwebber652 on December 8, 2024 at 1:05 am

    Other than calcium and magnesium do u get anything extra from diy process like micro nutes ?

  18. @Inland909 on December 8, 2024 at 1:05 am

    Guess I’m the only 1 didn’t get any questions answered w this video

  19. @Stonerman135 on December 8, 2024 at 1:06 am

    Do I use calmag every watering or every other watering like with other nutrients?

  20. @diabetekAFA on December 8, 2024 at 1:06 am

    can you use cal mag in the seedling phase?

  21. @rickfonseca2346 on December 8, 2024 at 1:08 am

    LMAO it’s either a calcium deficiency or a magnesium deficiency. No such thing as a Cal-mag deficiency. 😂

  22. @nonymontana626 on December 8, 2024 at 1:09 am

    Using it the right way an not puting alot in ur water wont harm thats how i use it i just throw a bet les then what it says with the food an i never had a problem she ben green an healthy

  23. @BrianM-44041 on December 8, 2024 at 1:09 am

    I’m already using tap water, azomite, ground eggshells, epsom salts, and bio char, so I have no need to add calmag. There is no such thing as a calmag deficiency, calcium and magnesium are separate nutrients and both show deficiency differently. Calmag is not the answer to every issue. Proper watering and a super soil mix should eliminate the need for calmag unless you’re running RO water or distilled. In hydro, aero, or an inert medium such as coco , rockwool, dwc, etc this is a totally different animal. If you’re in soil do not run out and waste money on calmag unless you see a deficiency, which I’ve never had in decades of growing. Keeping your substrate at the proper ph is also hugely important to uptake of nutrients as well. I recommend 5.5 to 6.5 in veg and flower. 6.2 works for me in flower well. Chalk is almost entirely gypsum calcium as is drywall board if you’re looking for cheap amendments. Diatomaceous earth is good for silica if you would like to add that cheaply. Calmag is a tiny amount of active ingredients and the rest is just water in a plastic bottle. Dolomite and gypsum lime as well as oyster shell calcium, azomite, calcium silicate, wood ash, bone meal, etc are all good sources of calcium for plants. Always check your other nutrients for calcium and magnesium content before adding any randomly. Calcium is good for many plant processes and also chelating some a well as balancing pH. Magnesium is necessary but a little goes a long way so don’t overdo that either. A tiny amount of Epsom salts a few times during veg and in the initial soil mix will probably provide plenty of mag and sulfur for the entire grow.

  24. @jeffbeerkens5286 on December 8, 2024 at 1:10 am

    Gaia green rock dust blend 👌🏼

  25. @God_is_good_ on December 8, 2024 at 1:10 am

    Jesus loves you all, God Bless✝️🍃

  26. @kievitman on December 8, 2024 at 1:12 am

    can u use calmag in the flower stage…

  27. @ZOMGbies on December 8, 2024 at 1:13 am

    ml to gallons. lmao pick a metric. dont fuck about with this gallon bullshit, its not 1812

  28. @Nihlink on December 8, 2024 at 1:17 am

    Idk i just use biobizz and everything works fine.

  29. @bigga1977 on December 8, 2024 at 1:19 am

    Nice one

  30. @BuffaloEskate on December 8, 2024 at 1:19 am

    He says use 5ml to start the FIRST couple times.. but then says that you should START with 1-2 ml then says START with 1-3 ml, doesn’t he? 😮😢

  31. @scottwebber652 on December 8, 2024 at 1:20 am

    I’ve been cought twice with expired cal mag. No date seen ever on label so going to diy but would like feedback on how to do the micro nutes needed. Response requested. Thanx

  32. @les-qy9lv on December 8, 2024 at 1:20 am

    👎 TOO MUCH JARGA
    Get to the POINT…

  33. @cannilony on December 8, 2024 at 1:21 am

    Never used it.

  34. @daSiew on December 8, 2024 at 1:21 am

    I dont get why you are mixing Imperial with Metric…

  35. @TimJameson-jg8sl on December 8, 2024 at 1:23 am

    Two words…stash blend

  36. @jiggyjay682 on December 8, 2024 at 1:23 am

    Okay for some reason I didn’t think I should use Cal-Mag during Flowering.. Now I know I can lol

  37. @stevenhunt9563 on December 8, 2024 at 1:24 am

    Can cal mag be used in first four weeks(stretch) of flower?

  38. @German_Growdiary on December 8, 2024 at 1:25 am

    Such a important content 👏

  39. @Brandon-v3t on December 8, 2024 at 1:27 am

    I live in an area that has alkaline water so the pH gets to the point where magnesium can’t be absorbed any more i just pH balance the water with bone meal because it’s super high in phosphorus which is acidic

  40. @Spiderdan-59 on December 8, 2024 at 1:28 am

    My plants are my babies I’m the only male that goes near them 🫡🌿🌿🔥🇬🇧

  41. @fangan4770 on December 8, 2024 at 1:29 am

    I always collect 5-10 eggshells and put them dried in the blender. I mix the powder into my soil. I have never had a Cal-Mag deficiency in my plants.

  42. @hanswurst1125 on December 8, 2024 at 1:31 am

    The infos are soo unprecise…

  43. @GMT439 on December 8, 2024 at 1:31 am

    How is it that I have never needed to use extra Cal Mag for decades but the internet seems to think I should be using it?
    Please Explain? As far as I see it, It is only for very rare occasions when it is required.

  44. @scottmcintee2660 on December 8, 2024 at 1:37 am

    How do u mix for frist feed

  45. @FelixDrolet-nz4yq on December 8, 2024 at 1:37 am

    Short and Sweet ! Always good contents

  46. @williamdonohue2004 on December 8, 2024 at 1:38 am

    I have been growing for 5 years. This year I have been using 5ml of cal-mag per gallon throughout the growing season. I’m now in the 4th week of flowering. All 6 plants are Granddaddy Purple. They are all very healthy and happy. This is my best grow yet. I’m not sure if it’s the cal-mag, but I am being very precise about the fertilizer and pH. Growing in 10 gallon cloth bags in Lucky Dog soil.

  47. @UncleDickeysRandomLife on December 8, 2024 at 1:40 am

    most soil ammendments recommend 5ml but half that is enough and feed 24 per week

  48. @ennyyyable on December 8, 2024 at 1:41 am

    what a waste of time this channel is..

    who are you targeting with this ish? kids? srsly come on now

  49. @masoncooper418 on December 8, 2024 at 1:45 am

    Ordered now

  50. @Nick-oh5dd on December 8, 2024 at 1:47 am

    Too much can turn your leaves yellow

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