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There is a blackberry bush in my garden, UK, its fruit is ripening at the moment, but many of them are discolored. I read that sunscald could be one cause, it does get direct sun for a lot of the day, and unfortunately I cannot move it as its too large. I have also wondered if it could be insects, but so far the only insects I have seen on the blackberries are one or two spiders, and what seems to be ants, who apparently only feed on already damaged blackberries. I have seen that the ants bulbous part on their body looks see through or partially see through on some them, but they do look just like ants. I have taken photos of the discoloration as well as the ants/insects. Is there any way to save the blackberries that haven't ripened yet? Some of the bunches of blackberries look almost 100% black like they should be, but many are like in the photo. thank you

The discoloration

enter image description here

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You may have a problem with raspberry beetle, which does affect blackberries too - it causes parts of the berries to dry up, as yours have done, although I've never seen whole berries so badly affected. Sunscald in the UK doesn't seem likely, but actually, the recent heatwave may have had some effect, though as its so recent, I suspect not. Its worth cutting open a few of the affected fruits, both those which are completely dry and those which are partially dry to see if there's a grub inside, which would confirm the presence of this pest. Information below

https://www.rhs.org.uk/advice/profile?PID=522

There is some possible evidence of red berry mite too, which causes uneven ripening of fruits, but that's difficult to identify for sure because its still relatively early and the fruits may not yet have fully ripened anyway. Information regarding this pest here

https://www.rhs.org.uk/advice/profile?pid=882

As for the presence of ants, they might be after damaged fruits for the their juice, or they may be present because of aphid infestation on the plant, so a close inspection to determine whether there are aphids anywhere is a good idea.

  • thank you very much for the information. just to say, those in the picture that are completely 100% tan/green are just those which haven't ripened yet. I have just cut open three from different areas which were badly affected, and I see no signs of worms/grubs or anything, aside from the discoloring I see nothing inside to indicate insects or an infestation. Though the mites specifically are microscopic so that would be very hard to see signs of. but the damage pictured on that link does not resemble the damage on my blackberries. pictures I've no seen of sunscald does look very close though. – insectsgoaway Jul 24 '16 at 12:50
  • Which part of the UK are you in? In London, we've had temps of 37degC during the last week, so if you're somewhere like that, sunscald is possible... blackberry fruits may also 'wither on the vine' so to speak if there's water shortage... – Bamboo Jul 24 '16 at 13:42
  • Im in Hampshire - we've had had some very sunny and humid/hot days here recently yeah. I heard that "white drupelets are caused by strong sun after periods of overcast weather", so this could be a possibility. ok, thank you for the info about withering. – insectsgoaway Jul 24 '16 at 13:49
  • Well that's about right 'periods of overcast weather', probably an understatement, then followed by sudden, very hot sun... shocked me, never mind your fruit! Shame though, hopefully you'll get some useable fruits. – Bamboo Jul 24 '16 at 15:03
  • haha yes, it has been a surprise. thank you. at least I could use those unsightly ones for jam or wine or something. – insectsgoaway Jul 24 '16 at 21:04
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You've got a heat problem, this is UV damage or excessive heat during the ripening phase and referred to as White Drupelet syndrome (white spot). It's quite common on Raspberries during the final crops of the year as summer heat increases. Also occurs in blackberries. Last year, we had issues in the US Pacific Northwest with it, only a handful at end of season this year as we've had a cold, damp summer.

  • ok thank you very much for the info! Its a big relief that it is purely weather related and not disease or insects! – insectsgoaway Jul 24 '16 at 21:03
  • I just found a little white worm inside one of the blackberries. I saw some damage on top of this particular blackberry but thought it was just slightly misformed or something like that. Damn! i.imgur.com/DQvPSgE.gif – insectsgoaway Jul 25 '16 at 18:34
  • Yeah, damaged berries become hosts to worms. Ick! – Fiasco Labs Jul 25 '16 at 19:15

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