Plant Diseases/Cucumber vine without fruits!
QUESTION: A huge number of tiny cucumbers in our garden suddenly turned yellow and just shrivel and fell off.We had seven cucumber vines and just a few mature fruits.Weird!Could it popossibly be a bacteria or fungi.Thanks indeed for Your answer, we are going to plant several vines this season.We sprinkled with copper but had no success...
If you see no evidence of spots or rotted areas to the young fruit. I suspect the dropping young fruit and being yellow may indicate an environmental issue rather than pathological (disease or insect). Small/immature fruit yellowing and dropping can be caused by incomplete pollination. This can be caused by a lack of an insect pollinator such as bees or it can be caused by high temperatures during pollination time. You may check for honey bee presence in your growing area while flowers are present. Sometimes too much Nitrogen in the plant can cause fruit drop, but i am leaning toward the insect angle.
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QUESTION: So I supose I have to plant them earlier because here in Croatia the summer is about 33°-35°C with spikes of 42°C.There are a lot of bees indeed so now after Your reply I am concerned obout temerature....
Thanks for your comments! Here in North Carolina, our last frost date in the spring is around April 15 or so. People are sometimes a bit too eager to get their vegetable plants in the ground and can loose them to a last minute cold event. So, here folks get their vegs planted early to avoid potential temperature issues. Not sure how your growing season is there. It is also very helpful to have some mulch around your cucs to avoid direct contact with the soil-- where some fungal organisms reside and can attack that fruit lying on the ground. Anything to keep the fruit off the bare soil can be helpful, plus mulch can conserve moisture in the soil. If you need to water your plants from overhead, try to do this early in the day so leaves dry off by mid day. This can reduce leaf spots caused by an assortment of bacteria and fungi. Try to avoid watering overhead late in the day or evening.
Have a great year.