A day of devastation

Aahh, Barbara Cartland ankles like a Queen Anne Chair, bow legs as well. no doubt.

Aahh, Barbara Cartland ankles like a Queen Anne Chair, bow legs as well. no doubt.

My dad had lathes both wood and metal, the phrase 'well turned ankle' had me imagining dad turning out ladies ankles to order. 

I don't think weedkiller would work that fast. How much potassium bicarbonate did you use? I usually stick with a 0.5% solution, so 5 grams per litre of water. Did you also use soap?

1 tablespoon to one gallon, ½ teaspoon soap (a bit of hand wash which might be the culprit) and a  ½ teaspoon of veg oil.  Whether its the soap or weedkiller residue I'm still stuffed.

So if 1 tbsp is about 15 g then that's about 3 g per litre, so that doesn't seem like the issue. That amount of soap doesn't seem like it should cause so much damage either, unless it contained some strong essential oils. Vegetable oil wouldn't do it either.

I have great respect for your scientific mind TMTT,  whilst I could have figured that dilution, it may have taken some time.  Does pottasium bicarb deteriorate into something harmful over a year?

I don't think so, it's basically baking soda with potassium instead of sodium. It will be stable until it gets wet or mixed with something acidic, but even then it won't produce any harmful by-products. You can use it in baking as a low salt alternative to baking soda.

Apart from being more effective, another reason it's used instead of baking soda in gardening/farming is that you don't want too much sodium going into the soil, whereas the extra potassium will benefit a lot of flowering plants.

I just weighed a tablespoon of my potassium bicarbonate and it was about 17 grams, so to be more precise, in a UK gallon that's a 0.37% solution which is well under what would be harmful to plants, and a lower concentration than I have used with no ill effects.

Armicarb is a fungicide used by organic farmers in Europe, and it's essentially potassium bicarbonate plus detergent and a wetting agent. The detergent is sodium lauryl sulphate, which is found in a lot of liquid hand wash.

I think it's likely that another ingredient in the hand wash is the culprit. My preference is unscented liquid castile soap, since it's pure soap and typically doesn't contain any other ingredients.

Does anyone think I should foliar feed the suffering courgettes or even just give the roots a liquid feed like miracle grow, or would that stress them even more?

I would give them a bit of a root feed. They might not take up nutrients properly via the leaves if they're droopy.

I covered the plants with fleece to protect them from sun and wind. Ive sprayed (with a clean hand mister and tap water) as many leaves as possible upper and lower side to perhaps help avoid transpiration. I will root feed tomorrow. Looking at them this afternoon I think its hormone weedkiller contamination as although the leaves look wilted they're actually deforming. The leaves are quite sturdy rather than flacid.

Here's some photos of my devastation

                                                        

I have no words. They were doing so well   . Even like that they’re still looking better than some I’ve grown in the past. 
I might be tempted to remove all the courgettes from the plants so they can use the energy they have on recovery. Rather than trying to reproduce.

My thoughts too. Then I can poison P too

Update, they're not dead yet and don't look much worse. The plan today, if I don't get rained off is to pick all the fruit and give them all a feed.
It's very damp so perhaps they'll succumb to some fungus.  Do you think I ought to spray them?