Attack of the Leaf Miners
This summer the lovely Ileana of A Candy-Colored Life sent me a packet of ‘Erbette’ chard seed as part of the Punk Rock Garden Swap. ‘Erbette’ has slender, pale green stems and delicate leaves that remind me more of spinach than Swiss chard. It is an elegant and sophisticated vegetable, just like its name suggests.
Which is why I was devastated to discover that an army of leaf miners decided they like ‘Erbette’ as much as I do. Leaf miners are the larvae of a tiny black fly. They wiggle their way in between the upper and lower leaf surfaces of chard (and other leafy greens), mine out a pocket, and leave ugly blisters all over the leaves.
They are totally gross and I have decided to wage war.
My garden is 100% organic, so I definitely wasn’t about to break out a spray to annihilate these icky pests. I did a little research and found out that the best way to deal with leaf miners is to cut out infested leaves as soon as you notice damage and dispose of them.
I’ve been vigilantly removing infested leaves and so far, so good! The number of leaves affected is diminishing quickly. Next year, I think that I’ll put a row cover over my chard (and spinach) in early summer when the leaf miner flies are out and about laying eggs. The row cover (which is an agricultural fabric that lets light and water in but keeps bugs out) will protect my pretty plants without using a drop of chemicals. Won’t that be nice?
I’ve had some issues with these pests also, on beets and spinach. I pick then out as I see them and I think that does a decent job.
September 13th, 2008 at 8:38 amI am so sad for you and the leaf miners. When I see their bodies convulsing in the leaves I want to puke. I actively despise them. I stopped growing spinach because no matter where I planted them, crop rotation, and even taking years off, I would seem to have a problem and I am just too grossed out by them to try again. Sad because I love fresh spinach. They also liked my beets this year but I picked them out like you suggested and that was ok, but I don’t eat beet greens. Still, they are the grossest veggie pest out there, bar none.
September 17th, 2008 at 5:51 pmI have a hard time with leaf miners as well and makes growing chard less than fun. In addition to picking the damaged parts off I have also has success seeking and destroying the little white eggs that they lay on the underside of the leaves. They are small but visible to the naked eye. They look like a little row of 4-6 white burritos laying side by side. I just wipe the eggs off of the leaves. Check out a photo of the the leaf miner eggs here:http://nomad.yosemite.net/?p=676
March 24th, 2010 at 8:12 pmThe chenopod family is affected by the leaf miner.
Knowing the life cycle of the pest helps. The spring hatch (May) and the fall hatch (August and September) are the bad times for infestation. The fall hatch is worst of the two.
Row covers are best, but temps can get too warm for spinach and chard. It’s easy to destroy the eggs but a daily check is needed to keep things from getting out of hand.
I don’t know if Neem is effective. I’ve heard that a new organic insecticide with Spinosad might address leaf miners.
March 29th, 2010 at 9:07 amMark–I agree. Learning the life cycle of a pest is really one of the best steps in learning how to control problems organically.
April 2nd, 2010 at 8:00 amI too have had leafminer problems, so much so that I gave up on chard. Picking off the impacted leaves left no leaves b/c they eventually would get every one. (Neem doesn’t work, btw — neither does any other spray b/c the insect is inside the leaf.) I am using row covers for the chard and kale this year — it’s a pain in the butt, but it works. Both crops are completely free of pests. The Kale in particular looks fantastic — the leaves are perfect in a way that I have never seen Kale look before.
June 1st, 2010 at 4:07 pm