I have noticed black patches on my boskoop Glory grapes. They are just about at the swelling stage and most bunches have these black marks on them. I fear I have lost the grapes for this season as I have never noticed this before. I do know that grapes do not like to be touched so maybe when I sprayed earlier in the season the pressure in my sprayer was too strong and has bruised the bunches of grapes. Has anyone got any ideas? The marks are not stains and do not rub off,I only sprayed with washing up liquid as I had an invasion of green and white fly ??? Thank you for your time
Dunno... I'll bump it back up for more exposure... :)
Hmm..difficult one that..any fungal stuff would quite likely show some signs on leaves too.
One thing that comes to my mind is..if the plant is suffering from drought and/or being temperature related..that could send some 'wrong messages'..sort of skipping from setting the fruit to ripening..with lack of water the fruit don't swell and instead it is trying to mature when still small... :-\
We've had 'wrong' temperatures for the times of year so far..anything could be expected really..
Quote from: goodlife on June 23, 2011, 13:02:59
Hmm..difficult one that..any fungal stuff would quite likely show some signs on leaves too.
One thing that comes to my mind is..if the plant is suffering from drought and/or being temperature related..that could send some 'wrong messages'..sort of skipping from setting the fruit to ripening..with lack of water the fruit don't swell and instead it is trying to mature when still small... :-\
We've had 'wrong' temperatures for the times of year so far..anything could be expected really..
Good point,it was really dry and hot here in mid April,with hardly any rain. Then most of May and the first couple of weels of June have been wet,very wet. I had temperature swings of 108 down to 38 in my polytunnel during mid April's afternoon and morning periods. The vine is four years old now,so I would think the tap root is well established by now,so not entirely convinced of your theory,but it is certainly as good a thought as any I've heard. Thanks for your time.
Grapes would not like that sort of temperature swing, especially at the top end when it would require an immense amount of moisture.