SOIL Calcium Deficiency?

[ponzi314]

So this i my first indoor grow, Im growing in Live Soil and have been just adding water. Up until now the plants have looked great and no issues. Now that im coming to the end im noticing brown spots on the top leaves. I looked at "Plant Problems" section and think its due to a calcium deficiency.

Can i get away with doing nothing or am i at the risk of killing the plant? It doesnt seem to be too bad. Its only on the front plant too.

[3Berries]

Calcium is one of the most important minerals for the plant to build with. If you don't add some it will only get worse. But you need something that is immediate or quick acting. Limestone works but is too slow reacting. It's good for adding to the initial soil. There is a 'dissolved' limestone that you can get, mixes easily with water but still is limestone, Nutrilime DG. Calcium Acetate or Calcium Chloride will both work immediately as foliar sprays or added to the soil at 1300 ppm.

[ponzi314]

Thank you, do you think this will work?

https://www.amazon.com/ENVY-Professional-Magnesium-Superior-Chloride/dp/B0952NNCNV/ref=sr_1_8?crid=382Q45KS4A723&keywords=calmag&qid=1670597705&sprefix=calmag%2Caps%2C148&sr=8-8&th=1

Im assuming i just add to the water when im watering

[3Berries]

yes that works

[OldManGrower]

Personally I'm lazy. Just add some cal-mag about a teaspoon per gallon. Dissolves instantly and works rapidly.

[AGH]

Whatever you decide to do, if you're growing in living soil/organic, you need to be super careful about what you put in the soil. When growing organic, you're not really so much tending the plant so much as you're tending the soil and the microbiome that it supports. Many synthetic nutrients/supplements (including Cal/Mag) will kill all the wonderful bacteria and fungi that you've nurtured. That's bad because in a living soil setup, the fungi and bacteria are what get the nutrients to the plant. If you kill them off with synthetic additions, you'll likely be sad. When growing weed, nothing good ever happens quickly. That's even more true when growing organic.

Do a quick Google search for 'sources or organic calcium for plants' and you'll find lots of options from dolomite lime and other items mentioned in other replies to simple things you have in your kitchen like egg shells. Although this will take a little bit of time to break down and become available for the plant, you'll be preserving your soil biome. And from the looks of your plants, you still have several weeks before harvest.

For future living soil grows, it is important to know that the 'water only' technique is only partly true. You still need to add organic teas and do top dressing so that you're keeping enough nutrients in the soil. If you re-run genetics, you'll hopefully take notes so you'll know that this particular strain needed more calcium or nitrogen or whatnot so you can make sure that it's in the soil (organically) and ready to go for your plants. For example, my Blue Dream needs LOTS of nitrogen in veg stage. I didn't know that the first time, so I ran into a deficiency. But the next time I ran those genetics, I was able to be proactive and make sure that I supplemented with N before it was needed since, as I said things take time, especially in organic soil grows.

Be patient, fix what you can, and you'll be prepared for the next grow!

[ponzi314]

dang, she was looking so pretty too. Atleast my other one doesnt seem to have this issue, Once i get the lime ill be able to catch it early one. do you recommend adding to top soil or adding to water and then watering.

[AGH]

Try a little of Column A and a little bit of Column B. As a rule of thumb, things dissolved in the water are more readily available to the plant and things that are topdressed into the soil are more 'slow-release'. Be careful not to overdo it though...don't want to create a nutrient lockout. That's generally harder to do in organic grows since the fungi and bacteria help give the plant what it needs but not impossible. There are likely instructions on the bag - use those as a guideline (or half that much if you want to be careful) and go from there.

[ponzi314]

Thank you AGH!

[3Berries]

I got a grow in ProMix BX that I've added limestone to and been using 50/50 well water, I figure that is about 800 mg per gallon of Ca.

At ~30 days the Ca deficiency started to show up in the new growth. Growing like crazy with high CO2. Yesterday I foliar fed it a 1300 ppm solution of CaCl and overnight most of the yellowing went away. Today I hit it again and also went to full well water at about 1600 mg a gallon Ca. They are getting about a quart at time for watering.

The yellow is only at the new growth at the top. In the past when this happened if I let it go then they brown out.

[3Berries]

Never had any light burn from droplets on the leaves. And I avoid doing it when the lights are off because it really raises the humidity. Only running about 120w now. I would imagine if you had a couple 1000 watts then light burn may be an issue due to the magnification of the water drop.

[AGH]

You have very possibly already considered this, but could your lights be too close/too intense? If new growth is starting out and staying yellow/brown/crispy that could be why. The foliar feeding could be combating that by providing the extra boost that they need to 'keep up' with all the food (light) that they're getting.

Could be worth a little experiment to see if backing the light off a little prevents the trouble with new growth and the need for the foliar sprays.

But then again, you may have already considered this, so feel free to ignore the above :-p

[3Berries]

I've raised the lights. But the yellow goes away after the foliar feed for the day.