For the past few years, leafminer has become a bigger problem each year. Last year my daylilies look so bad because of leafminer I vowed to try to do something this year to solve the problem.
Now, I am not saying the problem is solved, but it is definitely over 90 percent better than it was last year...once again, I can not say it is definitely due to something I have done. Could be the weather, or other natural causes. However,
due to the weather forecast the weather for the next three days looks favorable for spraying. I thought I would go double check the progress. Even though I am out in the garden everyday, I seem to have a one track mind and don't seem to be able to focus but on one task at a time, so I have to make special trips out to check on everything.
So I did find some leaf miner damage, but it was only on a few plants and only one or two leaves per plant. Now that is a huge improvement over almost every plant and almost every leaf and with more than one mine per leaf on many.
I purchased a quart of Abamectin 0.15EC Select and I have sprayed once every two weeks for about three months now. I used 1/2 tsp. per gal. and I just want to say how pleased I am with the results.
I would love to know if anyone out there has had success with this product also, or if you have had success with any other product against daylily leafminer.

Larry, I haven't had a huge problem with leaf miner damage on my DL's, I sure have it on my Columbine, they're probably the tastiest leaves in the garden here. I also haven't tried Abamectin but am going to spray with Neem Oil. I'm going to try 2 tablespoons per gallon of water.

Good luck with the Neem Oil, I spoke with a man who told me he used a light weight agricultural oil and had good luck with it on leafminer and with reducing rust.

Robin have you seen leafminer on daylilies there? It's not the same insect that mines on columbine.

Columbine leafminer has been here for decades. Most of the damage is done after the plants flower. It sometimes kills some of the leaves, but doesn't kill the plants, so I ignore it.

Daylily leafminer showed up here the year after it appeared so obviously in the Houston National Convention gardens. Maybe it was here before, and I didn't notice.

Once I started noticing, it appeared to be scattered all through the beds. It has never developed to a significant problem. There are probably not as many generations here as in warmer climates.

I've never treated for it and don't expect to.

Ann (formerly Pat; too many Pats)

Sue I haven't seen much leaf miner damage on DL's. My Columbines get a double whammy with the miners drawing swirly shapes through the inner parts of the leaf and a little green caterpillar munches all around the perimeter giving the leaf a scalloped edge. They never like their artistic touches so they just keep on munching, to fix their mistakes. They fix their mistakes to the nubbins and the plant dies.

Thanks, Robin. The reason I asked is that I haven't seen the daylily leafminer here - yet. I expect it will arrive eventually and if it is already in Michigan it's getting close to Ontario. I don't know if anyone in Ontario already has it though. Since it was first discovered in Maine then it was not all that far from Canada to start with!

I had a lot of leafminers last year. I don't want to spray anything, so this year, I thought I would try sprinkling diatomaceous earth around the base of each plant to catch the second generation as they emerge from the earth. I am reporting that this did no good at all. I still have leaf miners and am resigned to them.

DeweyRooter said:I had a lot of leafminers last year. I don't want to spray anything, so this year, I thought I would try sprinkling diatomaceous earth around the base of each plant to catch the second generation as they emerge from the earth. I am reporting that this did no good at all. I still have leaf miners and am resigned to them.

According to the AHS page on the leafminer, they pupate still in the daylily, therefore DE on the earth around the base wouldn't seem to affect them.

"Pupation occurs in the larval tunnel, with the pupa appearing like a small (3-4mm), tan rice grain, under the surface, often near the leaf base"

https://daylilies.org/daylily-...

sooby said:

According to the AHS page on the leafminer, they pupate still in the daylily, therefore DE on the earth around the base wouldn't seem to affect them.

Well, I guess that explains it.

Thank you Larry. I try your method. Last year it was bad and I see some plants already have leafminer. Where can I buy it? I live in California, lots of restrictions.

Liliesmaniac,
I purchased mine online : I did not see anything about not shipping to California, but double check that.
https://www.pestrong.com/903-a...

This is a quote from their site:
"This is generic Avid 0.15 EC.
We may ship any Generic Brand (A.I Abamectin -- 1.9% or more) depends on current stock & availability, but mostly Abamectin 0.15 EC Select, Quali-pro Abamectin 0.15 EC, Timectin 0.15 EC."

Thanks Larry. I see some of my seedlings already have leafminer.