Hop leaf insect...

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Shropshire Lad

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As you can see from the attached photo, I have a lot of my leaves nibbled at by an insect - I live in the UK. Will this cause a problem for the hops and if so what can I do to eradicate them?
 

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As you can see from the attached photo, I have a lot of my leaves nibbled at by an insect. Will this cause a problem for the hops and if so what can I do to eradicate them?
Have you seen the bug? Also, it could cause an issue if it becomes substantial.

Neem oil is the usual go to for me and make sure you spray the underside of the leaves as well to kill any larva. This will also help a bit for future mildew issues.
 
Have you seen the bug? Also, it could cause an issue if it becomes substantial.

Neem oil is the usual go to for me and make sure you spray the underside of the leaves as well to kill any larva. This will also help a bit for future mildew issues.
I haven’t seen them, buddy. I wondered at first if it was snails but I’m sure that it isn’t.
 
Have you looked at the backside of the leaf to see if there are any eggs laid on them or larvae munching on them.

Your picture reminded me of one time many years ago when I had potatoes growing in my garden and the leaves were eaten like that. I think it was potato beetles. I got worse real quick and the leaves were completely gone in a week.

Are there no agriculture extension offices there you can contact?
 
It'll impair your hops if the leaves get entirely eaten. Insects chewing on plants does induce some stress in them. Sometimes that's good for flavors but more often probably not. It also makes plants more susceptible to disease and fungal infections.

Hard to believe there isn't a service there in the big city that helps home gardeners with identifying pests and suggesting methods for their control.

Are there no garden supply shops? Surely someone at them will know what to suggest for control of whatever is eating on your plants.
 
It'll impair your hops if the leaves get entirely eaten. Insects chewing on plants does induce some stress in them. Sometimes that's good for flavors but more often probably not. It also makes plants more susceptible to disease and fungal infections.

Hard to believe there isn't a service there in the big city that helps home gardeners with identifying pests and suggesting methods for their control.

Are there no garden supply shops? Surely someone at them will know what to suggest for control of whatever is eating on your plants.
I’ll ask next time I’m at the garden Centre, buddy. Thanks for the reply.
 
I had the same problem with my hops this year. I think I found the culprit, some kind of leaf miner and they are pretty good a hiding out it seems. Anyway, whatever they were, I sprayed them with a ogranicly approved bio control product called Captian Jacks Deadbug, and the level of damage being done went down right away.
 
I had the same problem with my hops this year. I think I found the culprit, some kind of leaf miner and they are pretty good a hiding out it seems. Anyway, whatever they were, I sprayed them with a ogranicly approved bio control product called Captian Jacks Deadbug, and the level of damage being done went down right away.
Captain jacks dead bug is a great insecticide, that said it should not be used if flowering. It’s quite toxic.
 
Captain jacks dead bug is a great insecticide, that said it should not be used if flowering. It’s quite toxic.

It is toxic to many insect species, very low to no toxicity to mammals. Active ingredients are Spinosad A and and Spinosad C. Both are derived from naturally occurring soil bacteria. Spinosad listed as OK to use on flowering and fruiting crops and organically certified.

That said, there is a few days suggested wait period between application and consumption of crops, and I also don't recommend using when pollinators are present, even though some tests have concluded it is of low toxicity to bees (not sure I believe that).
 
It is toxic to many insect species, very low to no toxicity to mammals. Active ingredients are Spinosad A and and Spinosad C. Both are derived from naturally occurring soil bacteria. Spinosad listed as OK to use on flowering and fruiting crops and organically certified.

That said, there is a few days suggested wait period between application and consumption of crops, and I also don't recommend using when pollinators are present, even though some tests have concluded it is of low toxicity to bees (not sure I believe that).
We’ve been selling captain jacks at our nursery/greenhouses for about 10-15 years. I do understand that it is organic and derived from bacteria, that said it is one of the few organic compounds at market that the general public can purchase that can kill harb body insects. I understand they market it as low risk to humans but they do not specify if that is contact or ingestion.
With hops your going to use 2-3 lbs of wet flower in a beer. That can quickly increase concentrations.


We never recommend using captain jacks during fruiting to any of our customers. As a reminder, organic does not mean safe, it means made in nature. Rattle snake venom, arsenic, and night shade are all organic, but will kill you at the correct dose.

Also as a reminder, round up didn’t have a clear hazardous label until about 2010.
 
I'm in the the trade as well, 36 long years and with a Plant & Soil degree (for what that is worth, LOL). I actually read the label again before responding to your first comment. I stand by using it on hops, especially this time of year. Besides the fact it was not sprayed on flowers, harvest time is a couple months out.

I don't particularly trust Bonide, but it is similar to more holistically marketed 1st gen Spinosad products. Or maybe they are lying, and it is also dosed with Sevin. (joke, hopefully)

For the record, I'd not use 2-3 lbs of wet hops in my beer, no way, too much grassy chlorophyll taste. Dried and vacuum packed for me, besides, if they are not dried, they're going to be full of critters.

Organic can indeed be toxic, but in the case of this and other "organic" approved chemicals, break down time is usually faster than synthetics. And yeah, I know all about glyphosate. We don't even use it on driveways any more, but still have a big jug of 42% for occasional PI clearing.

I appreciate the conversation on this however, and am keeping an open mind.
 
I haven’t seen them, buddy. I wondered at first if it was snails but I’m sure that it isn’t.
Coming late to this, but at least with a UK perspective - that kind of "spatter" damage in the middle of leaves is generally slugs/snails (more likely snails given the dry weather). Caterpillars tend to leave fewer, "holier" holes, and attack both the middle and edge of the leaf - they eat with mouths at the end of their heads, whereas slugs/snails eat with more of a grinding motion from a "mouth" some way down their underside, which doesn't work so well on edges. Also you're more likely to catch caterpillars in the act as they tend to live on the leaves, whereas slugs/snails tend to disappear into walls etc during the day and come out at night to feed.

Just as a general comment, you're usually better off asking "gardening" questions over on the UK forums, you tend to get a lot of well-meaning comments here that just don't apply to the UK. To take some examples :

We don't have government ag extension offices here - our equivalent, ADAS, was privatised in 1997. But the Royal Horticultural Society provides an equivalent service for home gardeners and www.rhs.org.uk is an excellent place to start for all things pest and disease (in fact I used to work with the guy who was until recently their head of plant health).

We don't have Japanese beetles or potato beetles, in fact we're quite paranoid about keeping out the latter.

Neem oil - well, technically the active ingredient azadirachtin - has a rather complicated regulatory history in the EU, but to cut a long story short, it's effectively banned in the UK for retail garden use.

But anyway - it's probably snails, so neem oil is irrelevant anyway.
 
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