Not a pretty picture

Baby Colorado potato beetles

In today’s field photo selection, there was a kinda cool shot of a last-season carrot starting to flower, a freshly hand-weeded onion patch looking quite sharp, or this shiny, slimy cluster of baby Colorado potato beetles, going to town on a Black Beauty eggplant…

Pests and disease have thankfully not been a big problem in this organic field. I like to think that the garden is in some sort of balance, but perhaps it’s just location and luck… In either case, there have been some outbreaks: many tomato hornworms on the…tomatoes in Year 1, same for Colorado potato beetles on potatoes, early blight on tomatoes three years ago when the summer was cool and almost always cloudy and damp, and, of course, the everpresent flea beetles (brassicas) and striped cucumber beetles (cucurbits).

The FBs and CBs are defended against with floating row cover. The rest have recently died down, to the point where I let them do their thing, handpicking a few, but really accepting a small amount of leaf damage (they all eat leaves) and no plant loss.

This year, the CPBs seem to have crossed over to eggplant (another of their natural targets, but one they never really took aim at in the past). They seem to be favoring the Black Beauty eggplant…

The worst of the major damage in the photo happened in probably less than a day, as I’d taken a walk through there just yesterday. Only about four or five of 60+ Black Beauties had a significant presence, with a few loner CPBs on other varieties (and I’d noticed no eggs on the leaves in earlier checks). So, I squished ’em. Vigilance is somewhat increased.

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23 thoughts on “Not a pretty picture”

  1. You’re obviously not in the UK . Whereabouts is your tiny farm? I love some of your ideas and your loacl farmers market sounds (and looks) brilliant.

  2. We had the same problem with CPBs, I don’t think birds will eat orange and black bugs. I put lots of blue bird boxes around my garden and have a bird feeder within 20 feet to atract birds to the bugs.

    I don’t know if sulfur powder will kill Colorado Potato Beettles, but we had a really bad chigger problem about June and five pounds of Sulfer dust at dawn seemed to wipe them out of the tomatoes in one day!

    I wondered where the CPB were coming from, because they were there from the first season we had a garden there, then I found them in the horse pasture eating on wild night shade plants… they just had to migrate about 100 yards to get to the potatoes.

  3. Those CPBs are devouring my eggplants!  I’ve been pulling them off by hand for a week now, and smashing them, just to arrive a few hours later to another complete infestation.  The neighbors across the street are growing potatoes, so I assume they keep coming from there (?).   I sprayed with Neem, and no affect whatsoever.  Today I plucked them off and put them in a jar of rubbing alcohol, and to my surprise filled up 1/3 of the jar!  I’ve also found them on my heirloom tomatoes (not as bad, though), but they are taking out a few branches like a horn worm.    I just sprinkled Bt on there, after removing all the adults.  We’ll see if that has any affect on the larvae coming up.  Gosh, I sure hope so, I really want some eggplants to store for the upcoming winter.

  4. SunshineNDirt: It’s a year since this post, and the CPBs are on the eggplant again, not too bad, but they did feast on some leaves. I squish off the eggs when I find ’em, kinda pinch the leaf and roll ’em off with my thumb. Dunno if that’s the best approach, but it works, and I don’t use pesticides, even organic ones.

  5. I’ve been using diatamaceous earth, sprinkled on my potatoes. It’s been working really well so far. I also sprinkle it on my cucumbers and summer squash for the cucumber beetles. The tiny silica cystals have pointy edges that make tiny holes in the shell of the bugs which is supposed to disrupt their body’s moisture levels (i believe). You should avoid breathing it in because the crystals also irritate our respiratory passages.

  6. Shannon: I’ve tried diatomaceous earth. The thing is, unless you dust ’em directly, it all depends on how long the DE sticks around to actually come in contact with the beetles. It’ll be dispersed by rain, wind, dew… Unless you’re really infested with CPBs, and you have a fairly small area, I found it’s a lot quicker and easier to hand pick ’em. Checking for and removing the eggs is also good, but if you miss the eggs and get a newborn invasion, when they’re in the slimy, sticky, orange, soft shell stage (babies!), you can just shake the plants to knock ’em off onto the ground, and they don’t seem to be able to make it back. I went through the DE with proper duster applicator bit, but it seemed too expensive and time-consuming for the couple thousand feet of potatoes I grow. On eggplant, I just look for eggs and pick ’em as well.

    For cucurbits (cukes, squash, etc), I tried at the same time, with even less success. I guess it depends on the weather and the pest level. The cucumber beetles fly around a lot, so the chances of hitting ’em seem lower. Then it’s a matter of how long the DE remains on the leaves. I’ve had leaves almost white with DE (an experiment), and still had CBs…

    As for most things, for diatomacous earth, I guess your mileage varies…

  7. Diatomaceous earth is a good idea to try.  I’ve heard they dehydrate from them, but you do have to reapply it constantly, also good on slugs & snails. 

    I tell you, I’ve been hand picking those CPBs off for over a week now and have to do it every few hours.  I go out about 4 times a day and can pull off another 20 or so.  I’ve removed a whole entire jar so far.  It’s tedious and takes a lot of my time to do it.  

    I can’t tell if the babies can’t get back up the stalk, but from what I’ve read, they a born near the soil, but they seem to cluster in groups.  I haven’t found any eggs at all, but lots of larvae.  The Bt seems to work on the babies – give it a few days to work, and there seems to be fewer babies today.   It’s funny, a few years ago, eggplants was one of my best harvests – easy and fruitful.  Not this year!

  8. SunshineNDirt: Yeah, handpicking can get crazy in bad years, but there’s that or…products. Four times a day sounds like a LOT, where aer they coming from? If you’ve rotated your eggplant so there aren’t CPBs emerging right from the ground eggplant, you could have tried row cover when you put them in, but now, once the CPBs are under there, you’ll still have problems and have to remove the cover to pick.

    The problem I’ve had with the only applied stuff I’ve used, diatomaceous earth (I haven’t used organic controls like BT or pyrethrin or rotenone), is that you have to keep using it. This also takes time and costs, and could do as much harm as good eventually, because they’re not too selective. Like, DE kills off beneficial bugs, including non-hard bodied, like even bees, so if you’re dumping a fair bit of it on to kill a CPB invasion, you could be causing other problems. Like, I believe ladybugs eat CPB eggs, and DE will kill ladybugs… (Coincidentally, a comment just appeared on another post, also about CPBs, and asking about ID-ing CPB eggs vs ladybug eggs in order not to kill off ladybugs…)

    It sounds like you’re sticking to organics and as low-impact methods as possible, so you should read up on the CPB life cycle, and next year at least, try to get craftier with timing, like getting the eggs when they come out (spring and again once or twice a season), or shaking the larva off when they’re small, and maybe some sort of trap crop…

    When you’re having a big problem, chemicals can sound easy…! Luckily, I haven’t run into a BIG one that couldn’t be solved otherwise…so far!

  9. I live in an area with a McCain French fry plant in the east end of town and a Simplot one west of town. So, needless to say, I have a LOT of CPB to deal with. Last year, after handpicking for the beginning of the season I had to admit defeat and use Entrust. It’s expensive, but organic and I have to say, worth it. I wish I had used it earlier.

    This year I will start the season by putting kelp into the hole with the seed potato and see if that helps (an oldtimer told my friend about this and it has worked so far for her, but another friend says he tried it and it didn’t work for him), then spray with kelp fertilizer throughout the year, coupled with handpicking. If that doesn’t work, it’ll likely be Entrust again…but only as a last resort.

    I will also dust the rows with potatoes & eggplants in them with DE. I, like you Mike, also worry about my lovely ladybugs and other beneficials. DE only works on the adults though. No effect on the instars at all, and they are the ones that do the most damage as your photo clearly illustrates!

    My housemate’s dad said that he once was at an early baseball tournament and while drinking beer between games in the trees beside the fields they noticed a whole mound of CPB, likely coming out of hibernation. He said they were crawling all over each other, like ants. So another thing I’m going to do this year is go into the bush looking for them, armed with a shovel and bucket of soapy water. Then I will check myself thoroughly for woodticks :)  never ending! LOL

    If anyone finds anything that works really well, please post!
    Cheers, and good luck for a great season!

  10. Last year I had a bad infestation of CPBs, though the potatoes seemed to make it through OK.  This year I’m going to hill the potatoes once, then spread straw 4-6 inches thick and cover them w/ a floating row cover until the plants are pretty well developed.  Some folks around here (central Wis) had quite a problem last year and suggested these ideas.  I’m going to give this combination of techniques a try.

  11. Probably the single most effective thing to do about CPBs is to get familiar with their life cycle. Here’s a good CPB page, it’s concise, clear, illustrated. When it’s clear what’s going on, it’s usually easier to observe and do things with effective timing.

    A couple of years when I had lots of CPBs, I started by removing eggs.  You check the underside of leaves and what I did was kind of roll-scrape them off with my fingers. It’s a bit of a pain if you have lots of plants, but you’ll be eliminating 10-30 at a time, which isn’t bad compared to playing catch-up later.

    Even better is to eliminate as many as possible of  the first wave of adults as or before they mate. That means really monitoring for their first appearance in late April-May. If you’ve rotated your crop (you always should!), the CPBs won’t be coming directly out of the ground, so they’ll usually start appearing at the edges of your patch (if the patch is big enough to have edges! :), working their way in. I’ve watched them head down the rows over a few days. It’s pretty obvious. If you can get them before they’re wandering around laying a zillion eggs, that’d be good.

    Another thing I’ve tried is knocking the larva off the plants, instead of picking them. I hadn’t heard about this, maybe for a reason, like, it doesn’t work! Still, I’ve done it for a couple of years when the CPBs weren’t around in force. Especially if you get them early on (you can easily judge the larval stage they’re at by appearance, see the life cycle page linked to earlier), seems to me they’d have a hard to impossible time of getting back on the plants. I’ve quickly shaken out rows of plants, and not seen a return.

    In any case, it’s a really good idea to read about the CPB life cycle, kinda get inside their little insect heads! How cold-blooded… :)

  12. Mike,
    I couldn’t agree with you more. Three years ago I did a lot of research on their life cycle. I figured to catch a CPB ya gotta think like a CPB!

    Maybe we should moonlight for CSIS!?! lol

  13. That was my first year growing eggplants, and I’m not sure where they came from,except my neighbor across the street grows a lot of potatos.  She says she uses Sevin dust, but I’m pretty sure that’s not organic.

    This year I passed on growing eggplants, and watched my squash plants get devoured by another type of yellow beetle. 

    The diatomaceous earth needed to be reapplied constantly, since I live in an area it rains a lot. 

    I do rotate my plants every year, but I think they just come from my neighbors place who grows lots and lots of potatoes.  Ugh.

  14. OK, update time.
    The kelp in the hole didn’t work for me.
    I hand-picked my 700 plants and the only time the beetles got ahead of me was when I had to go away for 3 days…when I got home I had to spend over an hour in there picking for the next few days. I found this season that if you wait until the sun is out they seem to be out more. This was good for me b/c it’s a pretty low energy activity and one more easily done in the heat of the day.
    Picked and killed the adults (I used two rocks at the end of the rows called the CPB Cemetery) and squished the instars as I went along with my gloves on. If I kept on top of them, things were ok, but it did take time out of each day, except on harvest days…sometimes they were a bit worse the day after harvest day.
    You’re right, they will just migrate from your neighbour’s place.
    Diatomaceous earth only works on the adults, btw. And always protect your nose and mouth when using it b/c it contains a high % of silica which can cause lung damage.

  15. I have an idea for CPB control. I plan to water down some waffle syrup, spray it on the potato leaves, then sprinkle Diatomaceous earth on the wet syrup. I plan to do this at the first sign of CPB.

    Wish me luck.

  16. Last year I tried Chrysanthemum dust on the leaves during the larval stage and had absolutely NO trouble for the rest of the season.  And I had some good eggplants, finally!
     

  17. I finally had to plant things that BUGS don’t eat here  (OKLAHOMA). Nothing you can do to stop them.
    I’ve tried everything.
    Here’s my list of things that work here:
    Spinach
    Bush bean
    Bell Pepper
    Okra
    Onions
    Sweet potato
    Marigold
    Mustards
    Chard
    APPLE
    Pear
    Plum
    Sometimes you just adapt or die. Or better yet you move away from them!
     

  18. I have heard from a lady who grows organic spuds that she waits until just before sunset and then hits all the plants with a stick, knocking the CPBeetles to the ground. According to her there is something that comes out of the soil at night that attacks the bugs and kills them. She says she’s used this method for many years and it works for her. I will be trying this method, although I only have a small patch of potatoes this year and all my eggplants are under cover, so I don’t anticipate any bugs on them.

    Interested as to whether or not the diluted syrup worked too. I would hazard a guess that the leaves might fry in the hot sun with syrup on them.

    @Belowzero: I don’t think you can actually move away from these little buggers! :)

  19. Pingback: Organic Pest Control: Neem tops growers’ list | Enviro Strides
  20. by cultivation of other crop we can get good yield from potato field, this is my new research in this regard and i am sure it is true, if your intrusted sent me email and i will tell you name of second crop

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