Leaves curling/cupping, possibly calcium deficiency?

[ray_koots89]

First time growing and ran into this situation with the leaves curling downwards. I searched the ftt site but wasn't able to find anything, so I hope this post can help someone who's facing a similar issue.

From what I've seen and read online this is the primary sign of calcium deficiency in field plants, which is mainly caused by the depletion of calcium around the roots due to their lack of growth relative to the leaves and shoot, apparently not uncommon after a heatwave.

These are Virginia bright leaf plants growing in 3 gallon pots. Half are growing in promix vegetable potting mix, the other half are growing in a mix of peat moss, top soil, and sheep manure. I used a standard dose of the shake and feed miracle grow tomato fertilizer back in late May when they were last repotted. I use faucet water, it has high alkalinity (~170 mg/L calcium carbonate) and a pH of 8 or so, and I think is the cause of what's happening with the leaves.

I'm wondering if these are worth curing or not. The last photo is of one of the slack sea samsun plants, which so far hasn't shown symptoms like the bright leafs.

Thanks all, appreciate any help and insights into this,

 

[deluxestogie]

Welcome to the forum. Feel free to introduce yourself in the Introduce Yourself forum.

I use faucet water, it has high alkalinity (~170 mg/L calcium carbonate) and a pH of 8 or so, and I think is the cause of what's happening with the leaves.

You are likely correct about the cause. I see both cupping (Ca++ deficiency) as well as signs of frenching (generalized mineral deficiency). Both are indications of nutritional deficiencies which are sometimes caused by an actual deficiency. More often, the pH is outside the 5.5 to 6.2 ideal range, so the roots are unable to absorb the nutrients that are present.

A soil pH meter can easily settle the issue. It's fairly late in the season for an acidifying supplement, such as sulfur, to have a great impact this season. As for the affected leaf being worth harvesting, if they are large enough to seem worthwhile, I would be inclined to harvest and cure them—if for no other reason than seeing how they turn out.

Bob

 

[johnny108]

Perhaps adjust the ph of the water with some citric acid?

 

[Knucklehead]

I use these RV filters to remove the chlorine. It works inline with garden hose fittings. I don't know if the screen size is small enough to reduce calcium or not, but you could look into it or contact the manufacturer. I have noticed a reduction in water spots when I use it to wash the car. It definitely helped with chlorine, I used test strips for that.

https://www.amazon.com/gp/product/B07Z7ML4LW/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&th=1

 

[ray_koots89]

I use these RV filters to remove the chlorine. It works inline with garden hose fittings. I don't know if the screen size is small enough to reduce calcium or not, but you could look into it or contact the manufacturer. I have noticed a reduction in water spots when I use it to wash the car. It definitely helped with chlorine, I used test strips for that.

https://www.amazon.com/gp/product/B07Z7ML4LW/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&th=1

Thanks for the recommendation, I picked up a couple of these today. I figure cleaner water is a bonus, whether they remove the calcium or not.

 

[ray_koots89]

Just posting an update for anyone curious. As much as I've learned about micronutrient deficiency, the cause is more than likely contaminated manure.

My tomato plants started showing similar symptoms as the tobacco and it seems the culprit is most likely herbicide carryover in the manure used.

The math adds up. Since the initial posting the plants have grown another foot or so, and the differences between the manure mix plants and the promix plants are more obvious, I think because the tomatos and oriental varieties are less sensitive to the herbicide. Delayed damage during growth can probably be contributed to the double transplanting which created a soil buffer of sorts.

Pics for comparison:


Virginia Gold: Manure/peat mix on left, promix on right




Black Sea Samsun: Promix on left, manure on right




Tomato plant with herbicide damage

 

[dogfish858]

Most likely due to your location it's a combination of soil overheating, too high soil organics, too acidic of soil, resulting in nutrient imbalances.

Most compost sold in our end of the world is useless garbage. Most manure sold in our end of the world is mixed with wood chips or sawdust, especially B.C. It's basically just dirt-colored sawdust. It's great as mulch but near useless for planting unless you want blueberries or to tan hides with it or something like that.

I had to deal with the same thing a couple seasons before I figured out that compost isn't necessarily a good thing. It can be repaired by mixing it 50/50 or 30/70 with regular garden dirt.

That pic of the tomato I would say with some certainty is not herbicide damage, it's compost damage. Trial it with beans as they are the most sensitive.

 

[ray_koots89]

Most likely due to your location it's a combination of soil overheating, too high soil organics, too acidic of soil, resulting in nutrient imbalances.

Most compost sold in our end of the world is useless garbage. Most manure sold in our end of the world is mixed with wood chips or sawdust, especially B.C. It's basically just dirt-colored sawdust. It's great as mulch but near useless for planting unless you want blueberries or to tan hides with it or something like that.

I had to deal with the same thing a couple seasons before I figured out that compost isn't necessarily a good thing. It can be repaired by mixing it 50/50 or 30/70 with regular garden dirt.

That pic of the tomato I would say with some certainty is not herbicide damage, it's compost damage. Trial it with beans as they are the most sensitive.

Soil pH tests place it somewhere between 6.5 and 7. Snow peas are using the same manure mix but aren't showing symptoms.

https://extension.tennessee.edu/publications/Documents/W290-B.pdf

This article seems to indicate the cause is 2,4-D

 

[deluxestogie]

Tobacco soil pH should ideally be in the range of 5.7 to 6.2-6.5. Many herbicide damage symptoms are similar, regardless of the specific chemical.

Bob

 

[dogfish858]

I would suggest that the roots are overheated and pot bound resulting in biological and chemical 'static' where every potential negative is increased by the temp and lack of new resources. In my garden tomato leaf cupping is a heat thing, too, with certain types being more prone to it.

Stick a bbq thermometer into the side of your pots at heat of day and see what the temp is.

If it was herbicide your peas *should* show it before anything else, being legumes; legumes are the test for residuals.

That all said, I don't doubt it's herbicide residual. It wouldn't be surprising at all. There's so much of it in everything now that I only use what compost I can mix and source myself. Nothing from a bag and nothing from the store. Chicken manure, fish, leaves, garden waste, rabbit manure. Dairy and feedlot are out unless I know the guy. Legumes have to be able to grow in it. A fair quantity of phosphate and calcium, not much nitrogen. I also use JADAM JMS, which works extremely well as a remedial.

You can see in my pics how my Canik is cupping and sucking nutrients from the lower leaves as the pot becomes root bound and runs out of calcium, compared to my other Canik a few feet away.

 

[dogfish858]

...later that night the nice plants got trashed by hail...

 

[ray_koots89]

I would suggest that the roots are overheated and pot bound resulting in biological and chemical 'static' where every potential negative is increased by the temp and lack of new resources. In my garden tomato leaf cupping is a heat thing, too, with certain types being more prone to it.

Stick a bbq thermometer into the side of your pots at heat of day and see what the temp is.

If it was herbicide your peas *should* show it before anything else, being legumes; legumes are the test for residuals.

That all said, I don't doubt it's herbicide residual. It wouldn't be surprising at all. There's so much of it in everything now that I only use what compost I can mix and source myself. Nothing from a bag and nothing from the store. Chicken manure, fish, leaves, garden waste, rabbit manure. Dairy and feedlot are out unless I know the guy. Legumes have to be able to grow in it. A fair quantity of phosphate and calcium, not much nitrogen. I also use JADAM JMS, which works extremely well as a remedial.

You can see in my pics how my Canik is cupping and sucking nutrients from the lower leaves as the pot becomes root bound and runs out of calcium, compared to my other Canik a few feet away.

The pots were very warm to the touch, soil was luke warm and the roots are right against it, top to bottom.

Not sure about the peas, they were early flowering Alaskan type, so maybe they're hardier or just weren't in there long enough to see any effects.

My plants definitely resembled yours, as they drew taller the leaves became like straps, an inch or 2 wide, dark green, and very sticky.

I'll work on some sort of heat shield for the remaining healthy plants.