Overcome Calcium Deficiency In Your Garden

You open your tent to check on your ladies and see this problem. Little brown spots on the leaves cause calcium deficiency, but you don’t pay it any mind. Then, a few days later, the leaves show more signs of brown spots, which keep worsening. Has calcium deficiency ever happened in your garden? calcium deficiency What you have going on can be a few things, but most of the time, it’s a calcium deficiency, and in this video, I will cover how to treat calcium deficiency in your plants and the steps to take to get things back on track. I’m Cartier Crops, your home growers guide, and before we get into the guts of the topic, hit the subscribe button, bell button, text yo momma button, and follow all we do so you can gain the knowledge needed to flower better crops. Also, check out our website cartiercrops.com to join the community of like-minded growers who learn from other experienced and respectful home growers.


You’ve probably heard the term calmag getting thrown around anytime there’s a problem with your plants because calcium and magnesium play a massive role in growing cannabis. Calcium deficiency is rare if you’re growing outdoors, but Yo A$$ betta pay attention if you’re growing indoors. calcium deficiency If you’re a coco coir or hydroponics grower, you may find more problems than usual. You may be using organic soil, and this is a plus since most soils carry sufficient amounts of calcium, but you will run into issues if your pH and ppm are off. Before I share with you what I use and how to treat a calcium issue, let’s look at the causes of calcium deficiency and how to spot a problem with these three tips.

calcium deficiency1) Brown spots on cannabis leaves 

You will see small brown spots on the leaves, and you might get this confused with fungus, so make sure you dont have a bacterial infection before you dive deep. You’ll know if it’s calcium since it’s semi-mobile, meaning it will travel through the plant but not like the big 3 NPK. When you see brown spots turn into larger blotch sites spreading toward the edge of the leaf, then you can be sure it’s calcium.

calcium deficiency

2) Stems and Branches are Weak

You will notice slow growth along with stems and branches snappy and break easy. This is because the end of the root is dying, and the uptake of calcium is not doing its dizam thang!

3) Yellowing Leaves

Young shoots crinkle and become yellow or purple, and in severe cases, they will twist before they die.


Hydro growers, your roots will be brown and slimy from the bacteria attracted to the root system as the roots die. You might think you have a harmful bacteria issue, but the problem started with a lack of calcium in the water, killing the roots leading to deadly bacteria taking over.

So why is Calcium so essential, and how do we know it’s working as it should? 

Calcium in cannabis is vital to the plant’s stem walls and aids in root growth. Since calcium is semi-mobile, it will move slowly and concentrate on the roots and older leaves. You also want enough calcium towards the end to help with the uptake of Potassium to get that sticky icky flavor. You must be careful not to use calcium nitrate in mid flower; it’ll add more nitrogen to the feeding. Towards the end of a growing cycle, you want less nitrogen, so make a note of that and focus more on calcium carbonate like lime. For lime to work as it should, you want to make sure you till lime in before you start growing, so it’s active towards the end of your flowering cycle.

So how do we fix the calcium deficiency problems?

calcium deficiency Most indoor growers reach for the good ol cal-mag gets the job done. Many complete feeding schedules carry about 200 ppm of calcium, so if youre using city water, check levels before mixing more calcium into your reservoir, or you can be in excess and cause another problem. Now, If you want to fix a calcium issue instantly, you can make a foliar spray, and this is what I use and how I use the foliar spray when there’s a problem. Quick note, you will find links to Cal-mag supplements and other nutrient links in the description section below. Calcium Nitrate is a water-soluble fertilizer that supplies both Ca and N, and thats what cal-mag is. It is soluble, making it easy to use as a foliar spray for instant results.

Here is what I do to make a foliar spray with my cal-mag

  1. RO Water
  2. Use a spray bottle & 1-gallon jug
  3. Add 15 ml per gallon of cal-mag
  4. Mix well and test pH
  5. pH water to 6.3 – 6.5
    1. A higher pH level will help the uptake of calcium in the plant
  6. Pour the mixed solution into your spray bottle
    1. Spray once a day 3x per week
This simple trick will fix any calcium issues but be sure not to spray plants during the flowering stage. Plus, as I mentioned before, you want to stay away from nitrates in the flowering period and focus on magnesium. If you like to play with the soil, you can add ¼ cup of dolomite to the soil or coco coir. Be sure to mix well so you dont get any burns from excessive dolomite in one spot. Another benefit of using dolomite when making a potting mix is the pH balance of the media. Dolomite can help your soil or coco coir thrive from mid-veg through the middle flower if you know about pH swings.
All in all, calcium is vital to the growth of your plants and easy to spot. Keep in mind after week 4 of flowering, you will be cutting back on calcium nitrate and pushing more magnesium. If you watered your plant’s property with calcium nitrates, you would have enough nitrogen in the media to make it to the end of the process. Another thing to keep in mind is the pH level. If youre in soil, pH between 6.3-6.6 will help make the calcium available for the plants. calcium deficiency This is why hydroponics growers always have trouble with calcium since they need water to be acidic or below 6.0. So foliar spray if you’re in hydro and stay on top of the calcium supplement you add each watering. For more tips and information, head over to our website cartiercrops.com and sign up to be a member & join the community of new and experienced growers. You can find me there, and if social media sites get sideways, you can always find a home in our neighborhood. calcium deficiency I’m Cartier Crops guiding you to bigger, better-tasting crops without losing your mind and investment. Our private community helps you grow weed easily where you are the hero of your garden. For more cannabis deficiency tips Join Our Community below