Beneficial Insects

calico20hill · 2023-03-04T23:48:26+00:00

Thinking ahead to full bloom time, and topic of beneficial insects that eat the insects that damage our blooms....Has anyone tried interplanting dahlias wi...

PNWGal

calico20hill IN particular I see a lot of Soldier Beetles(?) BLack bugs about half an inch long that chew holes in petals.

Soldier beetles are good guys, and eat the bad bugs, not plants. Ours are narrow, with black bodies and red heads. Can you get a picture of the black bugs chewing holes in your plants?

Krista

KitCMC Oh I missed your comment about Queen Anne’s lace, we must have been hammering away at our comments at the same time. I grew up in southern Indiana and remember loving it in our horse pastures. It didn’t occur to me that it would be invasive here in WA so, thank you for this reminder! Nixing it from my list unless I can find a hole surrounded by cement like PNWGal.

calico20hill

Darn, I had forgotten the invasiveness of Queen ANne's Lace. Good reminder! I do love the dark version of it in bouquets but now that I think of it it grows wild all around here, but really runty since it is growing in the hard dry clay....and even that doesn't faze it!

MY worst pest Is... I think they are called Soldier Beetles, or something like that. ...Bigger then Lady Bugs and longer bodies. Its been a while since last summer and I can't remember exactly. I have absolutely NO problem with slugs but the ducks can't reach the upper parts of the dahlia plants so " fly in " bugs evade them.

If we ever get it done, there will be a perennial border on one side of the dahlia garden with lots of plants chosen to encourage butterflies and birds. I imagine a few of the dahlias might get nibbled by the larval stage of butterflies. I hope it all balances out.

Emilyp

calico20hill I use cilantro, dill and sweet alyssum for my beneficials, along with all the other annuals I grow. I release minute pirate bugs and green lacewings, and it has worked wonderfully for me in zone 5. The minute pirate bugs will give me a little nip now and then, but boy do they do a good job in the dahlias.

Krista

Emilyp I know our zones may make a difference, but when are you releasing the minute pirate bugs and green lacewings? I’m still considering bringing bugs in but I’m not sure when the best time to release who will be for bets results.

dahlia1972

Emilyp Do the lacewings eat the pirate bugs or vice versa?

blown_dry

If you have a mildish climate, fennel can also be an issue. It's a big problem invasive around here. I planted the bronze version in my garden and it's really hard to eradicate.

Krista

blown_dry in Seattle, garden varieties of fennel grown as a vegetable for their bulbs and foliage are different from the invasive varieties that are sown for pollen. Are both invasive in CA?

PNWGal

Ah, yes. The parking strip across the street is all bronze fennel & lemon balm. There is a stretch of bronze fennel growing wild along the railroad tracks too. Are annuals perhaps a safer way to go than perennials?

MissyWeitzel

I'm planning to do sweet alyssum, dill, and yarrow in planters around my beds. I have a lot of established yarrow in other areas so I'll just divide some and throw it in pots.
I tried using geraniums as a trap crop for the Japanese beetles last year but it didn't work. They love gerananiums and when the beetles chew on them, it paralyzes them for up to 12 hours, rendering them helpless for me to scoop into soapy water, other insects, or the elements. Unfortunately, when placed near my dahlias they decided they like dahlias more. Geraniums in the front yard had a lot of beetles though, so I guess I'll keep them up there. 🤪

Juliarugula

MissyWeitzel I tried using geraniums as a trap crop for the Japanese beetles last year but it didn't work.

My understanding is that’s it’s best to avoid anything that attracts them, even as a “trap”.

I’ve also heard recommendations to instead convince your further-away neighbors to plant the trap crops. 😈😜

addicted

Emily, I am also in zone 5 and have used green lacewings successfully for at least 5 years. I will have to try the pirate bugs as well, but have been delighted with the results of the green lacewings!

Emilyp

Krista I release them once I have an established area for them to live, once I have blooms and cover. I also stagger them, so that they don't eat each other immediately.

todgor

Each year I buy 18K lady bugs online and distribute them over my beds. There are online services to buy all sorts of beneficial insects. I was plagued with spider mites and aphids before I did this.

SteveM

My father grew completely organic and would order lady bugs a couple times a year. He would walk up and down the rows and place one lady bug on each of the plants. I remember he said it was important to already have an insect infestation so the lady bugs would have something to eat. Otherwise, they would fly away soom after they were released. They did a great job of controlling aphids for him.

calico20hill

Lots of good reminders here about not planting things that will become invasive. In the mild climates of western Oregon and we really can't count on winter kill of anything but tropicals. As for Aphids, I find that the lady bugs arrive soon after the aphids do and the problem is short lived. I'm aiming for that goal of encouraging butterflies and birds and I guess if I have them I have to be providing some of the food they like too. I guess I just need to know if there is something I should NOT be patient with if I see it in my garden. What plant or bug should I rip out of get rid of any way possible if I see it show up? SO FAR, at least, we do not have Japanese Beetles here. For which I am most grateful. A warming changing climate means that where the bugs invade and thrive will be changing too.

Juliarugula

calico20hill SO FAR, at least, we do not have Japanese Beetles here. For which I am most grateful

I had no idea there were parts of the US that were safe from the JB scourge! Lucky you!

I find that bagging blooms excludes JBs pretty well, and I don’t mind the extra work.

My most difficult pest to deal with is the tarnished plant bug, which can still manage to slip into the organza bags. From what I read, they have no known predator either. Let me know if anybody here has a good organic solution for them - we have quite a lot for most of our blooming season unfortunately.

blown_dry

Juliarugula Yes, I don't think they have reached CA at all. I expect the ag industry here will do what they can to keep it that way.

calico20hill

The beetles are only a few steps away from us now...its been great while it lasted.

blown_dry

I guess they monitor for them constantly here and eradicate any introductions. fingers crossed

NCDahlia

If anyone wants to permanently get rid of Japanese beetles... I highly recommend putting this down in the spring / fall called Milky Spore. Then the following year in spring. You get a 15 year barrier. It has cut my JB population down by 95% as well as voles no longer dig in my yard after the grubs because there are none. And rarely in the dahlia area.

https://www.arbico-organics.com/product/milky-spore-powder-bacillus-popilliae-control-japanese-beetle/early-spring-2023-new-featured-products?gclid=Cj0KCQiA9YugBhCZARIsAACXxeJKYOq1_SDn-Pt8rZB_3YLUbSWeh1Wjf1TehqA0C3u8BelrvjPnYCIaAisQEALw_wcB

They also have a spread broadcast ones like lawn fertilizer but its not as effective

Juliarugula

NCDahlia I’ve always hesitated to spend the money on milky spore because I live in a suburbanish neighborhood where all the lots are no more than a half acre. Seems like even if I take care of the grubs growing in my yard, there will be plenty from the neighbors.

Do you live further from other yards, or do you still feel it helps?

PegMc

Thanks for that share, NCDahlia! I discovered, quite by accident, that alfalfa pellets work for Japanese Beetles. I had a large order of Bearded Iris to plant and I use alfalfa pellets when planting. I had a plastic tub refilled with the pellets when a surprise torrential rain shower hit, so I grabbed up what I could and ran. I was slow to get back out there, but when I did I discovered Japanese Beetles floating all over the top of that tub!

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