Hi istara - There is no SVB problem with your plants. ;) Your plants have the classic look of too much water - soil that is kept too wet - and subsequent root rot as well as some nutrient deficiency. Those yellow leaves will eventually die and fall off but new growth will develop.

Container plants do require more frequent watering than in-ground plants do but it is easy to over do it too. Be sure to check the soil moisture level deep in the pot first rather than just assuming water is needed. And insufficient nutrient problems too are common with containers because the soil nutrients leach our of the container every time you water.

So I'd suggest you cut back on the watering and when you do water use a diluted mix of a well-balanced fertilizer every other time. 1/4 to 1/2 strength is the usual recommendation.

Good luck.

Dave

Thank you so much digdirt! I must have been killing it with love - when it started to yellow, I first worried that it was thirsty so gave it *more* water.

I guess it makes sense that a tiny curcurbit wouldn't need as much water as two-metre high tomato plant, so I'll have to start tailoring the feeding and watering a bit better ;)